Now we try to synchronously push updates as they come using the new rdv
point, so that the call to the server update function from the main poll
loop is not needed anymore.
It further reduces the apparent latency in the health checks as the response
time almost always appears as 0 ms, resulting in a slightly higher check rate
of ~1960 conn/s. Despite this, the CPU consumption has slightly dropped again
to ~32% for the same test.
The only trick is that the checks code is built with a bit of recursivity
because srv_update_status() calls server_recalc_eweight(), and the latter
needs to signal srv_update_status() in case of updates. Thus we added an
extra argument to this function to indicate whether or not it must
propagate updates (no if it comes from srv_update_status).
Multiplexers are not necessarily associated to an ALPN. ALPN is a TLS extension,
so it is not always defined or used. Instead, we now rather speak of
multiplexer's protocols. So in this patch, there are no significative changes,
some structures and functions are just renamed.
Now, a multiplexer can specify if it can be install on incoming connections
(ALPN_SIDE_FE), on outgoing connections (ALPN_SIDE_BE) or both
(ALPN_SIDE_BOTH). These flags are compatible with proxies' ones.
This function is generic and is able to automatically transfer data from a
buffer to the conn_stream's tx buffer. It does this automatically if the mux
doesn't define another snd_buf() function.
It cannot yet be used as-is with the conn_stream's txbuf without risking to
lose data on close since conn_streams need to be orphaned for this.
To be symmetrical with the recv() part, we no handle retryable and partial
transmission using a intermediary buffer in the conn_stream. For now it's only
set to BUF_NULL and never allocated nor used.
It cannot yet be used as-is without risking to lose data on close since
conn_streams need to be orphaned for this.
This is a partial revert of the commit deccd1116 ("MEDIUM: mux: make
mux->snd_buf() take the byte count in argument"). It is a requirement to do
zero-copy transfers. This will be mandatory when the TX buffer of the
conn_stream will be used.
So, now, data are consumed by mux->snd_buf() and not only sent. So it needs to
update the buffer state. On its side, the caller must be aware the buffer can be
replaced y an empty or unallocated one.
As a side effet of this change, the function co_set_data() is now only responsible
to update the channel set, by update ->output field.
When b_slow_realign is called with the <output> parameter equal to 0, the
buffer's head, after the realign, must be set to 0. It was errornously set to
the buffer's size, because there was no test on the value of <output>.
The current synchronization point enforces certain restrictions which
are hard to workaround in certain areas of the code. The fact that the
critical code can only be called from the sync point itself is a problem
for some callback-driven parts. The "show fd" command for example is
fragile regarding this.
Also it is expensive in terms of CPU usage because it wakes every other
thread just to be sure all of them join to the rendez-vous point. It's a
problem because the sleeping threads would not need to be woken up just
to know they're doing nothing.
Here we implement a different approach. We keep track of harmless threads,
which are defined as those either doing nothing, or doing harmless things.
The rendez-vous is used "for others" as a way for a thread to isolate itself.
A thread then requests to be alone using thread_isolate() when approaching
the dangerous area, and then waits until all other threads are either doing
the same or are doing something harmless (typically polling). The function
only returns once the thread is guaranteed to be alone, and the critical
section is terminated using thread_release().
When threads are disabled, some variables such as tid and tid_bit are
still checked everywhere, the MAX_THREADS_MASK macro is ~0UL while
MAX_THREADS is 1, and the all_threads_mask variable is replaced with a
macro forced to zero. The compiler cannot optimize away all this code
involving checks on tid and tid_bit, and we end up in special cases
where all_threads_mask has to be specifically tested for being zero or
not. It is not even certain the code paths are always equivalent when
testing without threads and with nbthread 1.
Let's change this to make sure we always present a single thread when
threads are disabled, and have the relevant values declared as constants
so that the compiler can optimize all the tests away. Now we have
MAX_THREADS_MASK set to 1, all_threads_mask set to 1, tid set to zero
and tid_bit set to 1. Doing just this has removed 4 kB of code in the
no-thread case.
A few checks for all_threads_mask==0 have been removed since it never
happens anymore.
An offsetof() macro was introduced with commit 928fbfa ("MINOR: compiler:
introduce offsetoff().") with a fallback for older compilers. But this
breaks gcc 3.4 because __size_t and __uintptr_t are not defined there.
However size_t and uintptr_t are, so let's fix it this way. No backport
needed.
The purpose is to make sure that all variables which directly depend
on this nbthread argument are set at the right moment. For now only
all_threads_mask needs to be set. It used to be set while calling
thread_sync_init() which is called too late for certain checks. The
same function handles threads and non-threads, which removes the need
for some thread-specific knowledge from cfgparse.c.
If nbthread is MAX_THREADS, the shift operation needed to compute
all_threads_mask fails in thread_sync_init(). Instead pass a number
of threads to this function and let it compute the mask without
overflowing.
This should be backported to 1.8.
Since BoringSSL 3b2ff028, API now correctly match OpenSSL 1.1.0.
The patch revert part of haproxy 019f9b10: "Fix BoringSSL call and
openssl-compat.h/#define occordingly.".
This will not break openssl/libressl compat.
Add a new pipe, one per thread, so that we can write on it to wake a thread
sleeping in a poller, and use it to wake threads supposed to take care of a
task, if they are all sleeping.
This lock was necessary to manipulate the pendconn element between
concurrent places, but was causing great difficulties in the list walk
by having to iterate over multiple entries instead of being able to
safely pick the first one (in fact the first element was always the
right one but the locking model was hard to prove).
Here since we know we can always rely on the queue's locks, we take
the queue's lock every time we need to modify the element. In practice
it was already the case everywhere except in pendconn_dequeue() which
only works on an element that was already detached. This function had
to be protected against the risk of meeting an incompletely detached
element (which could be unlinked but not yet assigned). By taking the
queue lock around the LIST_ISEMPTY test, it's enough to ensure that a
concurrent thread either didn't begin or had completed the operation.
The true benefit really is in pendconn_process_next_strm() where we
can again safely work with the first element of each queue. This will
significantly simplify next updates to this code.
The pendconn struct uses ->px and ->srv to designate where the element is
queued. There is something confusing regarding threads though, because we
have to lock the appropriate queue before inserting/removing elements, and
this queue may only be determined by looking at ->srv (if it's not NULL
it's the server, otherwise use the proxy). But pendconn_grab_from_px() and
pendconn_process_next_strm() both assign this ->srv field, making it
complicated to know what queue to lock before manipulating the element,
which is exactly why we have the pendconn_lock in the first place.
This commit introduces pendconn->target which is the target server that
the two aforementioned functions will set when assigning the server.
Thanks to this, the server pointer may always be relied on to determine
what queue to use.
Now pendconn_free() takes a stream, checks that pend_pos is set, clears
it, and uses pendconn_unlink() to complete the job. It's cleaner and
centralizes all the bookkeeping work in pendconn_unlink() only and
ensures that there's a single place where the stream's position in the
queue is manipulated.
For now the pendconns may be dequeued at two places :
- pendconn_unlink(), which operates on a locked queue
- pendconn_free(), which operates on an unlocked queue and frees
everything.
Some changes are coming to the queue and we'll need to be able to be a
bit stricter regarding the places where we dequeue to keep the accounting
accurate. This first step renames the locked function __pendconn_unlink()
as it's for use by those aware of it, and introduces a new general purpose
pendconn_unlink() function which automatically grabs the necessary locks
before calling the former, and pendconn_cond_unlink() which additionally
checks the pointer and the presence in the queue.
As __task_wakeup() is responsible for increasing
rqueue_local[tid]/global_rqueue_size, make __task_unlink_rq responsible for
decreasing it, as process_runnable_tasks() isn't the only one that removes
tasks from runqueues.
By removing the reason code for the wakeup we can gain 8 extra bits to
encode the task's state. The reason code was never used at all and is
wrong by design since subsequent calls will OR this value anyway. Let's
say it goodbye and leave the room for more precious bits. The woken bits
were moved to the higher byte so that the most important bits can stay
grouped together.
Whenever it's possible to avoid a copy, b_xfer() will simply swap the
buffer's heads without touching the data. This has brought the performance
back from 140 kH/s to 202 kH/s on the test case.
This function is generic and is able to automatically transfer data
from a conn_stream's rx buffer to the destination buffer. It does this
automatically if the mux doesn't define another rcv_buf() function.
In order to reorganize the connection layers, recv() operations will
need to be retryable and to support partial transfers. This requires
an intermediary buffer to hold the data coming from the mux. After a
few attempts, it turns out that this buffer is best placed inside the
conn_stream itself. For now it's only set to buf_empty and it will be
up to the caller to allocate it if required.
The latter function is more suited to operations that don't require any
check because the check has already been performed. It will be used by
other b_* functions.
This function is used a lot in block copies and is needlessly
complicated since it still uses pointer arithmetic. Let's fall
back to regular offsets and simplify it. This removed around
23 bytes from b_putblk() and it removed any conditional jump.
In thread_sync_barrier, we exit when all threads have set their own bit in the
barrier mask. It is done by comparing it to all_threads_mask. But we must not
use a simple equality to do so, becaue all_threads_mask may change. Since commit
ba86c6c25 ("MINOR: threads: Be sure to remove threads from all_threads_mask on
exit"), when a thread exit, its bit is removed from all_threads_mask. Instead,
we must use a bitwise AND to test is all bits of all_threads_mask are set.
This also requires that all_threads_mask is set to volatile if we want to
catch changes.
This patch must be backported in 1.8.
This new function wl_set_waitcb() prepopulates a wait_list with a tasklet
and a context and returns it so that it can be passed to ->subscribe() to
be added to a connection or conn_stream's wait_list. The caller doesn't
need to know all the insiders details anymore this way.
Totally nuke the "send" method, instead, the upper layer decides when it's
time to send data, and if it's not possible, uses the new subscribe() method
to be called when it can send data again.
Add a new "subscribe" method for connection, conn_stream and mux, so that
upper layer can subscribe to them, to be called when the event happens.
Right now, the only event implemented is "SUB_CAN_SEND", where the upper
layer can register to be called back when it is possible to send data.
The connection and conn_stream got a new "send_wait_list" entry, which
required to move a few struct members around to maintain an efficient
cache alignment (and actually this slightly improved performance).
Now all the code used to manipulate chunks uses a struct buffer instead.
The functions are still called "chunk*", and some of them will progressively
move to the generic buffer handling code as they are cleaned up.
Chunks are only a subset of a buffer (a non-wrapping version with no head
offset). Despite this we still carry a lot of duplicated code between
buffers and chunks. Replacing chunks with buffers would significantly
reduce the maintenance efforts. This first patch renames the chunk's
fields to match the name and types used by struct buffers, with the goal
of isolating the code changes from the declaration changes.
Most of the changes were made with spatch using this coccinelle script :
@rule_d1@
typedef chunk;
struct chunk chunk;
@@
- chunk.str
+ chunk.area
@rule_d2@
typedef chunk;
struct chunk chunk;
@@
- chunk.len
+ chunk.data
@rule_i1@
typedef chunk;
struct chunk *chunk;
@@
- chunk->str
+ chunk->area
@rule_i2@
typedef chunk;
struct chunk *chunk;
@@
- chunk->len
+ chunk->data
Some minor updates to 3 http functions had to be performed to take size_t
ints instead of ints in order to match the unsigned length here.
Now the buffers only contain the header and a pointer to the storage
area which can be anywhere. This will significantly simplify buffer
swapping and will make it possible to map chunks on buffers as well.
The buf_empty variable was removed, as now it's enough to have size==0
and area==NULL to designate the empty buffer (thus a non-allocated head
is the empty buffer by default). buf_wanted for now is indicated by
size==0 and area==(void *)1.
The channels and the checks now embed the buffer's head, and the only
pointer is to the storage area. This slightly increases the unallocated
buffer size (3 extra ints for the empty buffer) but considerably
simplifies dynamic buffer management. It will also later permit to
detach unused checks.
The way the struct buffer is arranged has proven quite efficient on a
number of tests, which makes sense given that size is always accessed
and often first, followed by the othe ones.
It used to be called 'len' during the reorganisation but strictly speaking
it's not a length since it wraps. Also we already use '_data' as the suffix
to count available data, and data is also what we use to indicate the amount
of data in a pipe so let's improve consistency here. It was important to do
this in two operations because data used to be the name of the pointer to
the storage area.
This one is more generic and designed to work on a random block. It
may later get a b_rep_ist() variant since many strings are already
available as (ptr,len).
There was no point keeping that function in the buffer part since it's
exclusively used by HTTP at the channel level, since it also automatically
appends the CRLF. This further cleans up the buffer code.
The new file istbuf.h links the indirect strings (ist) with the buffers.
The purpose is to encourage addition of more standard buffer manipulation
functions that rely on this in order to improve the overall ease of use
along all the code. Just like ist.h and buf.h, this new file is not
expected to depend on anything beyond these two files.
A few functions were added and/or converted from buffer.h :
- b_isteq() : indicates if a buffer and a string match
- b_isteat() : consumes a string from the buffer if it matches
- b_istput() : appends a small string to a buffer (all or none)
- b_putist() : appends part of a large string to a buffer
The equivalent functions were removed from buffer.h and changed at the
various call places.
The two variants now do exactly the same (appending at the tail of the
buffer) so let's not keep the distinction between these classes of
functions and have generic ones for this. It's also worth noting that
b{i,o}_putchk() wasn't used at all and was removed.
There's no distinction between in and out data now. The latter covers
the needs of the former and supports wrapping. The extra cost is
negligible given the locations where it's used.
Since we never access this field directly anymore, but only through the
channel's wrappers, it can now move to the channel. The buffers are now
completely free from the distinction between input and output data.
Since we use "_data" for the amount of data at many places, as opposed to
"_space" for the amount of space, let's rename the "data" field to "area"
so that we can reuse "data" later for the amount of data in the buffer
(currently called "len" despite not being contigous).
b_set_data() is used :
- in proto_http and hlua to trim input data (b_set_data(co_data()))
- in SPOE to append data to a buffer while building a message
In no case will this truncate a buffer so we can safely remove the
test for len < b->output.
b_del() is used in :
- mux_h2 with the demux buffer : always processes input data
- checks with output data though output is not considered at all there
- b_eat() which is not used anywhere
- co_skip() where the len is always <= output
Thus the distinction for output data is not needed anymore and the
decrement can be made inconditionally in co_skip().
This is intentionally the minimal and safest set of changes, some cleanups
area still required. These changes are quite tricky and cannot be
independantly tested, so it's important to keep this patch as bisectable
as possible.
buf_empty and buf_wanted were changed and are now exactly similar since
there's no <p> member in the structure anymore. Given that no test is
ever made in the code to check that buf == &buf_wanted, it may be possible
that we don't need to have two anymore, unless some buf_empty tests have
precedence. This will have to be investigated.
A significant part of this commit affects the HTTP compression code,
which used to deeply manipulate the input and output buffers without
any reasonable solution for a better abstraction. For this reason, if
any regression is met and designates this patch as the culprit, it is
important to run tests which specifically involve compression or which
definitely don't use it in order to spot the issue.
Cc: Olivier Houchard <ohouchard@haproxy.com>
For the same consistency reasons, let's use b_empty() at the few places
where an empty buffer is expected, or c_empty() if it's done on a channel.
Some of these places were there to realign the buffer so
{b,c}_realign_if_empty() was used instead.
We used to have variations around buffer_total_space() and
size-buffer_len() or size-b_data(). Let's simplify all this. buffer_len()
was also removed as not used anymore.
Now the new API functions are being used everywhere, we can get rid
of b_ptr(). A few last users like bi_istput() and bo_istput() appear
to only differ by what part of the buffer they're increasing, but
that should quickly be merged.
With this flag we introduce the notion of "dry" vs "wet" buffers : some
demultiplexers like the H2 mux require as much room as possible for some
operations that are not retryable like decoding a headers frame. For this
they need to know if the buffer is congested with data scheduled for
leaving soon or not. Since the new API will not provide this information
in the buffer itself, the caller must indicate it. We never need to know
the amount of such data, just the fact that the buffer is not in its
optimal condition to be used for receipt. This "CO_RFL_BUF_WET" flag is
used to mention that such outgoing data are still pending in the buffer
and that a sensitive receiver should better let it "dry" before using it.
The mux and transport rcv_buf() now takes a "flags" argument, just like
the snd_buf() one or like the equivalent syscall lower part. The upper
layers will use this to pass some information such as indicating whether
the buffer is free from outgoing data or if the lower layer may allocate
the buffer itself.
It also returns a size_t. This is in order to clean the API. Note
that the H2 mux still uses some ints in the functions called from
h2_rcv_buf(), though it's not really a problem given that H2 frames
are smaller. It may deserve a general cleanup later though.
Just like we have a size_t for xprt->snd_buf(), we adjust to use size_t
for rcv_buf()'s count argument and return value. It also removes the
ambiguity related to the possibility to see a negative value there.
This way the mux doesn't need to modify the buffer's metadata anymore
nor to know the output's size. The mux->snd_buf() function now takes a
const buffer and it's up to the caller to update the buffer's state.
The return type was updated to return a size_t to comply with the count
argument.
This way the senders don't need to modify the buffer's metadata anymore
nor to know about the output's split point. This way the functions can
take a const buffer and it's clearer who's in charge of updating the
buffer after a send. That's why the buffer realignment is now performed
by the caller of the transport's snd_buf() functions.
The return type was updated to return a size_t to comply with the count
argument.
Now that there are no more users requiring to modify the buffer anymore,
switch these ones to const char and const buffer. This will make it more
obvious next time send functions are tempted to modify the buffer's output
count. Minor adaptations were necessary at a few call places which were
using char due to the function's previous prototype.
Till now the callers had to know which one to call for specific use cases.
Let's fuse them now since a single one will remain after the API migration.
Given that bi_del() may only be used where o==0, just combine the two tests
by first removing output data then only input.
This will be important so that we can parse a buffer without touching it.
Now we indicate where from the buffer's head we plan to start to copy, and
for how many bytes. This will be used by send functions to loop at the end
of the buffer without having to update the buffer's output byte count.
This new functoin limits itself to the amount of data available in the
buffer and doesn't care about the direction anymore. It's only called
from co_getblk() which already checks that no more than the available
output bytes is requested.
These ones were merged into a single b_contig_space() that covers both
(the bo_ case was a simplified version of the other one). The function
doesn't use ->i nor ->o anymore.
This function was sometimes used from a channel and sometimes from a buffer.
In both cases it requires knowledge of the size of the output data (to skip
them). Here the split ensures the channel can deal with this point, and that
other places not having output data can continue to work.
These ones manipulate the output data count which will be specific to
the channel soon, so prepare the call points to use the channel only.
The b_* functions are now unused and were removed.
The few call places where it's used can use the trash as a swap buffer,
which is made for this exact purpose. This way we can rely on the
generic b_slow_realign() call.
Where relevant, the channel version is used instead. The buffer version
was ported to be more generic and now takes a swap buffer and the output
byte count to know where to set the alignment point. The H2 mux still
uses buffer_slow_realign() with buf->o but it will change later.
This adds :
- c_orig() : channel buffer's origin
- c_size() : channel buffer's size
- c_wrap() : channel buffer's wrapping location
- c_data() : channel buffer's total data count
- c_room() : room left in channel buffer's
- c_empty() : true if channel buffer is empty
- c_full() : true if channel buffer is full
- c_ptr() : pointer to an offset relative to input data in the buffer
- c_adv() : advances the channel's buffer (bytes become part of output)
- c_rew() : rewinds the channel's buffer (output bytes not output anymore)
- c_realign_if_empty() : realigns the buffer if it's empty
- co_data() : # of output data
- co_head() : beginning of output data
- co_tail() : end of output data
- ci_data() : # of input data
- ci_head() : beginning of input data
- ci_tail() : end of input data
- ci_stop() : location after ci_tail()
- ci_next() : pointer to next input byte
And for the ci_* / co_* functions above, the "__*" variants which disable
wrapping checks, and the "_ofs" variants which return an offset relative to
the buffer's origin instead.
Many places deal with buffer realignment after data removal. The method
is always the same : if the buffer is empty, set its pointer to the origin.
Let's have a function for this so that we have less code to change with the
new API.
Add a new function that lets you set the amount of input in a buffer.
For now it extends/truncates b->i except if the total length is
below b->o in which case it clears i and adjusts o.
Instead of doing b->i -= directly, introduce b_sub(), that does the job, to
make it easier to switch to the future API.
Also add b_add(), that increases b->i, instead of using it directly, and
bo_add(), that does increase b->o.
Here's the list of newly introduced functions :
- b_data(), returning the total amount of data in the buffer (currently i+o)
- b_orig(), returning the origin of the storage area, that is, the place of
position 0.
- b_wrap(), pointer to wrapping point (currently data+size)
- b_size(), returning the size of the buffer
- b_room(), returning the amount of bytes left available
- b_full(), returning true if the buffer is full, otherwise false
- b_stop(), pointer to end of data mark (currently p+i), used to compute
distances or a stop pointer for a loop.
- b_peek(), this one will help make the transition to the new buffer model.
It returns a pointer to a position in the buffer known from an offest
relative to the beginning of the data in the buffer. Thus, we can replace
the following occurrences :
bo_ptr(b) => b_peek(b, 0);
bo_end(b) => b_peek(b, b->o);
bi_ptr(b) => b_peek(b, b->o);
bi_end(b) => b_peek(b, b->i + b->o);
b_ptr(b, ofs) => b_peek(b, b->o + ofs);
- b_head(), pointer to the beginning of data (currently bo_ptr())
- b_tail(), pointer to first free place (currently bi_ptr())
- b_next() / b_next_ofs(), pointer to the next byte, taking wrapping
into account.
- b_dist(), returning the distance between two pointers belonging to a buffer
- b_reset(), which resets the buffer
- b_space_wraps(), indicating if the free space wraps around the buffer
- b_almost_full(), indicating if 3/4 or more of the buffer are used
Some of these are provided with the unchecked variants using the "__"
prefix, or with the "_ofs" suffix indicating they return a relative
position to the buffer's origin instead of a pointer.
Cc: Olivier Houchard <ohouchard@haproxy.com>
Passing unsigned ints everywhere is painful, and will cause some headache
later when we'll want to integrate better with struct ist which already
uses size_t. Let's switch buffers to use size_t instead.
The buffer code currently depends on pools and other stuff and is not
really autonomous anymore. The rewrite of the new API is an opportunity
to clean this up. This patch creates a new file (buf.h) which does not
depend on other elements and which will only contain what is needed to
perform the most basic buffer operations. The new API will be introduced
in this file and the conversion will be finished once buffer.h is empty.
The definition of struct buffer was moved to this new file, using more
explicity stdint types for the sizes and offsets.
Most new functions will be implemented in two variants :
__b_something() : unchecked variant, no wrapping is expected
b_something() : wrapping-checked variant
This way callers will be able to select which one to use depending on
the use cases.
Commit 200b0fa ("MEDIUM: Add support for updating TLS ticket keys via
socket") introduced support for updating TLS ticket keys from the CLI,
but missed a small corner case : if multiple bind lines reference the
same tls_keys file, the same reference is used (as expected), but during
the clean shutdown, it will lead to a double free when destroying the
bind_conf contexts since none of the lines knows if others still use
it. The impact is very low however, mostly a core and/or a message in
the system's log upon old process termination.
Let's introduce some basic refcounting to prevent this from happening,
so that only the last bind_conf frees it.
Thanks to Janusz Dziemidowicz and Thierry Fournier for both reporting
the same issue with an easy reproducer.
This fix needs to be backported from 1.6 to 1.8.
By default, HAProxy's DNS resolution at runtime ensure that there is no
IP address duplication in a backend (for servers being resolved by the
same hostname).
There are a few cases where people want, on purpose, to disable this
feature.
This patch introduces a couple of new server side options for this purpose:
"resolve-opts allow-dup-ip" or "resolve-opts prevent-dup-ip".
Up until now, a tasklet couldn't be free'd while it was in the list, it is
no longer the case, so make sure we remove it from the list before freeing it.
To do so, we have to make sure we correctly initialize it, so use LIST_INIT,
instead of setting the pointers to NULL.
The behavior of sigprocmask in an multithreaded environment is
undefined.
The new macro ha_sigmask() calls either pthreads_sigmask() or
sigprocmask() if haproxy was built with thread support or not.
This should be backported to 1.8.
To make sure we don't inadvertently insert task in the global runqueue,
while only the local runqueue is used without threads, make its definition
and usage conditional on USE_THREAD.
When building without threads enabled, instead of just using the global
runqueue, just use the local runqueue associated with the only thread, as
that's what is now expected for a single thread in prcoess_runnable_tasks().
This should fix haproxy when built without threads.
When an applet is created, let's assign it the same nice value as the task
of the stream which owns it. It ensures that fairness is properly propagated
to applets, and that the CLI can regain a low latency behaviour again. Huge
differences have been seen under extreme loads, with the CLI being called
every 200 microseconds instead of 11 milliseconds.
This function returns true is some notifications are registered.
This function is usefull for the following patch
BUG/MEDIUM: lua/socket: Sheduling error on write: may dead-lock
It should be backported in 1.6, 1.7 and 1.8
Don't forget to increase tasks_run_queue when we're adding a task to the
tasklet list, and to decrease it when we remove a task from a runqueue,
or its value won't be accurate, and could lead to tasks not being executed
when put in the global run queue.
1.9-dev only, no backport is needed.
This patch adds a warning if an http-(request|reponse) (add|set)-header
rewrite fails to change the respective header in a request or response.
This usually happens when tune.maxrewrite is not sufficient to hold all
the headers that should be added.
There's no real reason to have a specific scheduler for applets anymore, so
nuke it and just use tasks. This comes with some benefits, the first one
being that applets cannot induce high latencies anymore since they share
nice values with other tasks. Later it will be possible to configure the
applets' nice value. The second benefit is that the applet scheduler was
not very thread-friendly, having a big lock around it in prevision of this
change. Thus applet-intensive workloads should now scale much better with
threads.
Some more improvement is possible now : some applets also use a task to
handle timers and timeouts. These ones could now be simplified to use only
one task.
Introduce tasklets, lightweight tasks. They have no notion of priority,
they are just run as soon as possible, and will probably be used for I/O
later.
For the moment they're used to replace the temporary thread-local list
that was used in the scheduler. The first part of the struct is common
with tasks so that tasks can be cast to tasklets and queued in this list.
Once a task is in the tasklet list, it has its leaf_p set to 0x1 so that
it cannot accidently be confused as not in the queue.
Pure tasklets are identifiable by their nice value of -32768 (which is
normally not possible).
A lot of tasks are run on one thread only, so instead of having them all
in the global runqueue, create a per-thread runqueue which doesn't require
any locking, and add all tasks belonging to only one thread to the
corresponding runqueue.
The global runqueue is still used for non-local tasks, and is visited
by each thread when checking its own runqueue. The nice parameter is
thus used both in the global runqueue and in the local ones. The rare
tasks that are bound to multiple threads will have their nice value
used twice (once for the global queue, once for the thread-local one).
In preparation for thread-specific runqueues, change the task API so that
the callback takes 3 arguments, the task itself, the context, and the state,
those were retrieved from the task before. This will allow these elements to
change atomically in the scheduler while the application uses the copied
value, and even to have NULL tasks later.
A few users reported that building without threads was accidently broken
after commit 6b96f72 ("BUG/MEDIUM: pollers: Use a global list for fd
shared between threads.") due to all_threads_mask not being defined.
It's OK to set it to zero as other code parts do when threads are
enabled but only one thread is used.
This needs to be backported to 1.8.
The function hlua_ctx_resume return less text message and more error
code. These error code allow the caller to return appropriate
message to the user.
The polled_mask is only used in the pollers, and removing it from the
struct fdtab makes it fit in one 64B cacheline again, on a 64bits machine,
so make it a separate array.
With the old model, any fd shared by multiple threads, such as listeners
or dns sockets, would only be updated on one threads, so that could lead
to missed event, or spurious wakeups.
To avoid this, add a global list for fd that are shared, using the same
implementation as the fd cache, and only remove entries from this list
when every thread as updated its poller.
[wt: this will need to be backported to 1.8 but differently so this patch
must not be backported as-is]
Modify fd_add_to_fd_list() and fd_rm_from_fd_list() so that they take an
offset in the fdtab to the list entry, instead of hardcoding the fd cache,
so we can use them with other lists.
While running a task, we may try to delete and free a task that is about to
be run, because it's part of the local tasks list, or because rq_next points
to it.
So flag any task that is in the local tasks list to be deleted, instead of
run, by setting t->process to NULL, and re-make rq_next a global,
thread-local variable, that is modified if we attempt to delete that task.
Many thanks to PiBa-NL for reporting this and analysing the problem.
This should be backported to 1.8.
For large farms where servers are regularly added or removed, picking
a random server from the pool can ensure faster load transitions than
when using round-robin and less traffic surges on the newly added
servers than when using leastconn.
This commit introduces "balance random". It internally uses a random as
the key to the consistent hashing mechanism, thus all features available
in consistent hashing such as weights and bounded load via hash-balance-
factor are usable. It is extremely convenient because one common concern
when using random is what happens when a server is hammered a bit too
much. Here that can trivially be avoided, like in the configuration below :
backend bk0
balance random
hash-balance-factor 110
server-template s 1-100 127.0.0.1:8000 check inter 1s
Note that while "balance random" internally relies on a hash algorithm,
it holds the same properties as round-robin and as such is compatible with
reusing an existing server connection with "option prefer-last-server".
In order to use arbitrary data in the CLI (multiple lines or group of words
that must be considered as a whole, for example), it is now possible to add a
payload to the commands. To do so, the first line needs to end with a special
pattern: <<\n. Everything that follows will be left untouched by the CLI parser
and will be passed to the commands parsers.
Per-command support will need to be added to take advantage of this
feature.
Signed-off-by: Aurélien Nephtali <aurelien.nephtali@corp.ovh.com>
We'll need this in order to support uploading chunks. The h2 to h1
converter checks for the presence of the content-length header field
as well as the CONNECT method and returns these information to the
caller. The caller indicates whether or not a body is detected for
the message (presence of END_STREAM or not). No transfer-encoding
header is emitted yet.
In some cases, we call cs_destroy() very early, so early the connection
doesn't yet have a mux, so we can't call mux->detach(). In this case,
just destroy the associated connection.
This should be backported to 1.8.
With gcc < 4.7, when HAProxy is built with threads, the macros
HA_ATOMIC_CAS/XCHG/STORE relies on the legacy __sync builtins. These macros
are slightly complicated than the versions relying on the '_atomic'
builtins. Internally, some local variables are defined, prefixed with '__' to
avoid name clashes with the caller.
On the other hand, the macros HA_ATOMIC_UPDATE_MIN/MAX call HA_ATOMIC_CAS. Some
local variables are also definied in these macros, following the same naming
rule as below. The problem is that '__new' variable is used in
HA_ATOMIC_MIN/_MAX and in HA_ATOMIC_CAS. Obviously, the behaviour is undefined
because '__new' in HA_ATOMIC_CAS is left uninitialized. Unfortunatly gcc fails
to detect this error.
To fix the problem, all internal variables to macros are now suffixed with name
of the macros to avoid clashes (for instance, '__new_cas' in HA_ATOMIC_CAS).
This patch must be backported in 1.8.
In addition to metrics about time spent in the SPOE, following counters have
been added:
* applets : number of SPOE applets.
* idles : number of idle applets.
* nb_sending : number of streams waiting to send data.
* nb_waiting : number of streams waiting for a ack.
* nb_processed : number of events/groups processed by the SPOE (from the
stream point of view).
* nb_errors : number of errors during the processing (from the stream point of
view).
Log messages has been updated to report these counters. Following pattern has
been added at the end of the log message:
... <idles>/<applets> <nb_sending>/<nb_waiting> <nb_error>/<nb_processed>
Now it is possible to configure a logger in a spoe-agent section using a "log"
line, as for a proxy. "no log", "log global" and "log <address> ..." syntaxes
are supported.
With "log global" line, the global list of loggers are copied into the proxy's
struct. The list coming from the default section is also copied when a frontend
or a backend section is parsed. So it is possible to have duplicate entries in
the proxy's list. For instance, with this following config, all messages will be
logged twice:
global
log 127.0.0.1 local0 debug
daemon
defaults
mode http
log global
option httplog
frontend front-http
log global
bind *:8888
default_backend back-http
backend back-http
server www 127.0.0.1:8000
Now, the function parse_logsrv should be used to parse a "log" line. This
function will update the list of loggers passed in argument. It can release all
log servers when "no log" line was parsed (by the caller) or it can parse "log
global" or "log <address> ... " lines. It takes care of checking the caller
context (global or not) to prohibit "log global" usage in the global section.
"set-process-time" and "set-total-time" options have been added to store
processing times in the transaction scope, at each event and group processing,
the current one and the total one. So it is possible to get them.
TODO: documentation
Following metrics are added for each event or group of messages processed in the
SPOE:
* processing time: the delay to process the event or the group. From the
stream point of view, it is the latency added by the SPOE
processing.
* request time : It is the encoding time. It includes ACLs processing, if
any. For fragmented frames, it is the sum of all fragments.
* queue time : the delay before the request gets out the sending queue. For
fragmented frames, it is the sum of all fragments.
* waiting time: the delay before the reponse is received. No fragmentation
supported here.
* response time: the delay to process the response. No fragmentation supported
here.
* total time: (unused for now). It is the sum of all events or groups
processed by the SPOE for a specific threads.
Log messages has been updated. Before, only errors was logged (status_code !=
0). Now every processing is logged, following this format:
SPOE: [AGENT] <TYPE:NAME> sid=STREAM-ID st=STATUC-CODE reqT/qT/wT/resT/pT
where:
AGENT is the agent name
TYPE is EVENT of GROUP
NAME is the event or the group name
STREAM-ID is an integer, the unique id of the stream
STATUS_CODE is the processing's status code
reqT/qT/wT/resT/pT are delays descrive above
For all these delays, -1 means the processing was interrupted before the end. So
-1 for the queue time means the request was never dequeued. For fragmented
frames it is harder to know when the interruption happened.
For now, messages are logged using the same logger than the backend of the
stream which initiated the request.
Clearing the update_mask bit in fd_insert may lead to duplicate insertion
of fd in fd_updt, that could lead to a write past the end of the array.
Instead, make sure the update_mask bit is cleared by the pollers no matter
what.
This should be backported to 1.8.
[wt: warning: 1.8 doesn't have the lockless fdcache changes and will
require some careful changes in the pollers]
This function will be called from the CLI's "show fd" command to append some
extra mux-specific information that only the mux handler can decode. This is
supposed to help collect various hints about what is happening when facing
certain anomalies.
This patch add option crc32c (PP2_TYPE_CRC32C) to proxy protocol v2.
It compute the checksum of proxy protocol v2 header as describe in
"doc/proxy-protocol.txt".
