From 89eb0f46a4714c2ebdabd012966c6c3bb93e600c Mon Sep 17 00:00:00 2001
From: Shubham Taple <subbutaple@gmail.com>
Date: Sun, 5 Apr 2026 21:25:12 +0530
Subject: [PATCH 1/5] Improve time complexity of streamMoveIdmpKeys()

---
 src/cluster_asm.c |  3 ++-
 src/db.c          | 17 ++++++++++-------
 src/server.h      |  2 +-
 3 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/src/cluster_asm.c b/src/cluster_asm.c
index db801a9a1..f4a57ee46 100644
--- a/src/cluster_asm.c
+++ b/src/cluster_asm.c
@@ -3044,9 +3044,10 @@ void asmTriggerBackgroundTrim(asmTrimCtx *trim_ctx, int migration_cleanup) {
             kvstoreMoveDict(server.db[0].keys, keys, slot);
             kvstoreMoveDict(server.db[0].expires, expires, slot);
             estoreMoveEbuckets(server.db[0].subexpires, subexpires, slot);
-            streamMoveIdmpKeys(server.db[0].stream_idmp_keys, stream_idmp_keys, slot);
         }
     }
+    /* Move stream IDMP keys from main DB to temp dict (O(IDMP entries x number of slot ranges)) */
+    streamMoveIdmpKeys(server.db[0].stream_idmp_keys, stream_idmp_keys, slots);
 
     emptyDbDataAsync(keys, expires, subexpires, stream_idmp_keys, trim_ctx);
 
diff --git a/src/db.c b/src/db.c
index 1565b7bef..acb0cf788 100644
--- a/src/db.c
+++ b/src/db.c
@@ -1107,21 +1107,24 @@ void discardTempDb(redisDb *tempDb) {
     zfree(tempDb);
 }
 
-/* Move entries whose robj keys belong to the given slot from src dict to dst.
+/* Move entries whose robj keys belong to the given slotRangeArray from src dict to dst.
  * Matching entries are removed from src and added to dst. */
-void streamMoveIdmpKeys(dict *src, dict *dst, int slot) {
+void streamMoveIdmpKeys(dict *src, dict *dst, slotRangeArray *slots) {
     if (dictSize(src) == 0) return;
 
+    /* slots must not be NULL */
+    serverAssert(slots != NULL);
     dictIterator *di = dictGetSafeIterator(src);
     dictEntry *de;
     while ((de = dictNext(di)) != NULL) {
         robj *key = dictGetKey(de);
-        if (calculateKeySlot(key->ptr) == slot) {
-            if (dictAdd(dst, key, dictGetVal(de)) == DICT_OK) {
-                incrRefCount(key);
-            }
-            dictDelete(src, key);
+        /* Check if key belongs to the slot range. */
+        if (!slotRangeArrayContains(slots, keyHashSlot(key->ptr, sdslen(key->ptr))))
+            continue;
+        if (dictAdd(dst, key, dictGetVal(de)) == DICT_OK) {
+            incrRefCount(key);
         }
+        dictDelete(src, key);
     }
     dictReleaseIterator(di);
 }
diff --git a/src/server.h b/src/server.h
index 72036f6b6..65847162d 100644
--- a/src/server.h
+++ b/src/server.h
@@ -3998,7 +3998,7 @@ void scanGenericCommand(client *c, robj *o, unsigned long long cursor);
 int parseScanCursorOrReply(client *c, robj *o, unsigned long long *cursor);
 int dbAsyncDelete(redisDb *db, robj *key);
 void emptyDbAsync(redisDb *db);
-void streamMoveIdmpKeys(dict *src, dict *dst, int slot);
+void streamMoveIdmpKeys(dict *src, dict *dst, struct slotRangeArray *slots);
 void emptyDbDataAsync(kvstore *keys, kvstore *expires, ebuckets hexpires, dict *stream_idmp_keys, struct asmTrimCtx *ctx);
 size_t lazyfreeGetPendingObjectsCount(void);
 size_t lazyfreeGetFreedObjectsCount(void);

From f57ef334493a57ec4a7e1aa46c994a15e681308c Mon Sep 17 00:00:00 2001
From: Shubham Taple <subbutaple@gmail.com>
Date: Thu, 16 Apr 2026 22:23:47 +0530
Subject: [PATCH 2/5] Add test for asmTriggerBackgroundTrim, remove temporary
 EXPERIMENTAL tag from sflush.json and tcl

---
 src/commands.def                             | 36 ++++++++++
 src/commands/sflush.json                     |  3 +-
 tests/unit/cluster/multi-slot-operations.tcl | 76 +++++++++++++++++++-
 3 files changed, 112 insertions(+), 3 deletions(-)

diff --git a/src/commands.def b/src/commands.def
index 3980365d4..ecf5c7da6 100644
--- a/src/commands.def
+++ b/src/commands.def
@@ -8171,6 +8171,41 @@ struct COMMAND_ARG RESTORE_ASKING_Args[] = {
 #define SAVE_Keyspecs NULL
 #endif
 
+/********** SFLUSH ********************/
+
+#ifndef SKIP_CMD_HISTORY_TABLE
+/* SFLUSH history */
+#define SFLUSH_History NULL
+#endif
+
+#ifndef SKIP_CMD_TIPS_TABLE
+/* SFLUSH tips */
+#define SFLUSH_Tips NULL
+#endif
+
+#ifndef SKIP_CMD_KEY_SPECS_TABLE
+/* SFLUSH key specs */
+#define SFLUSH_Keyspecs NULL
+#endif
+
+/* SFLUSH data argument table */
+struct COMMAND_ARG SFLUSH_data_Subargs[] = {
+{MAKE_ARG("slot-start",ARG_TYPE_INTEGER,-1,NULL,NULL,NULL,CMD_ARG_NONE,0,NULL)},
+{MAKE_ARG("slot-last",ARG_TYPE_INTEGER,-1,NULL,NULL,NULL,CMD_ARG_NONE,0,NULL)},
+};
+
+/* SFLUSH flush_type argument table */
+struct COMMAND_ARG SFLUSH_flush_type_Subargs[] = {
+{MAKE_ARG("async",ARG_TYPE_PURE_TOKEN,-1,"ASYNC",NULL,NULL,CMD_ARG_NONE,0,NULL)},
+{MAKE_ARG("sync",ARG_TYPE_PURE_TOKEN,-1,"SYNC",NULL,NULL,CMD_ARG_NONE,0,NULL)},
+};
+
+/* SFLUSH argument table */
+struct COMMAND_ARG SFLUSH_Args[] = {
+{MAKE_ARG("data",ARG_TYPE_BLOCK,-1,NULL,NULL,NULL,CMD_ARG_MULTIPLE,2,NULL),.subargs=SFLUSH_data_Subargs},
+{MAKE_ARG("flush-type",ARG_TYPE_ONEOF,-1,NULL,NULL,NULL,CMD_ARG_OPTIONAL,2,NULL),.subargs=SFLUSH_flush_type_Subargs},
+};
+
 /********** SHUTDOWN ********************/
 
 #ifndef SKIP_CMD_HISTORY_TABLE
@@ -11910,6 +11945,7 @@ struct COMMAND_STRUCT redisCommandTable[] = {
 {MAKE_CMD("restore-asking","An internal command for migrating keys in a cluster.","O(1) to create the new key and additional O(N*M) to reconstruct the serialized value, where N is the number of Redis objects composing the value and M their average size. For small string values the time complexity is thus O(1)+O(1*M) where M is small, so simply O(1). However for sorted set values the complexity is O(N*M*log(N)) because inserting values into sorted sets is O(log(N)).","3.0.0",CMD_DOC_SYSCMD,NULL,NULL,"server",COMMAND_GROUP_SERVER,RESTORE_ASKING_History,3,RESTORE_ASKING_Tips,0,restoreCommand,-4,CMD_WRITE|CMD_DENYOOM|CMD_ASKING,ACL_CATEGORY_KEYSPACE|ACL_CATEGORY_DANGEROUS,RESTORE_ASKING_Keyspecs,1,NULL,7),.args=RESTORE_ASKING_Args},
 {MAKE_CMD("role","Returns the replication role.","O(1)","2.8.12",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,ROLE_History,0,ROLE_Tips,0,roleCommand,1,CMD_NOSCRIPT|CMD_LOADING|CMD_STALE|CMD_FAST|CMD_SENTINEL,ACL_CATEGORY_ADMIN|ACL_CATEGORY_DANGEROUS,ROLE_Keyspecs,0,NULL,0)},
 {MAKE_CMD("save","Synchronously saves the database(s) to disk.","O(N) where N is the total number of keys in all databases","1.0.0",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,SAVE_History,0,SAVE_Tips,0,saveCommand,1,CMD_NO_ASYNC_LOADING|CMD_ADMIN|CMD_NOSCRIPT|CMD_NO_MULTI,0,SAVE_Keyspecs,0,NULL,0)},
+{MAKE_CMD("sflush","Remove all keys from selected range of slots.","O(N)+O(k) where N is the number of keys and k is the number of slots.","8.0.0",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,SFLUSH_History,0,SFLUSH_Tips,0,sflushCommand,-3,CMD_WRITE,ACL_CATEGORY_KEYSPACE|ACL_CATEGORY_DANGEROUS,SFLUSH_Keyspecs,0,NULL,2),.args=SFLUSH_Args},
 {MAKE_CMD("shutdown","Synchronously saves the database(s) to disk and shuts down the Redis server.","O(N) when saving, where N is the total number of keys in all databases when saving data, otherwise O(1)","1.0.0",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,SHUTDOWN_History,1,SHUTDOWN_Tips,0,shutdownCommand,-1,CMD_ADMIN|CMD_NOSCRIPT|CMD_LOADING|CMD_STALE|CMD_NO_MULTI|CMD_SENTINEL|CMD_ALLOW_BUSY,0,SHUTDOWN_Keyspecs,0,NULL,4),.args=SHUTDOWN_Args},
 {MAKE_CMD("slaveof","Sets a Redis server as a replica of another, or promotes it to being a master.","O(1)","1.0.0",CMD_DOC_DEPRECATED,"`REPLICAOF`","5.0.0","server",COMMAND_GROUP_SERVER,SLAVEOF_History,0,SLAVEOF_Tips,0,replicaofCommand,3,CMD_NO_ASYNC_LOADING|CMD_ADMIN|CMD_NOSCRIPT|CMD_STALE,0,SLAVEOF_Keyspecs,0,NULL,1),.args=SLAVEOF_Args},
 {MAKE_CMD("slowlog","A container for slow log commands.","Depends on subcommand.","2.2.12",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,SLOWLOG_History,0,SLOWLOG_Tips,0,NULL,-2,0,0,SLOWLOG_Keyspecs,0,NULL,0),.subcommands=SLOWLOG_Subcommands},
diff --git a/src/commands/sflush.json b/src/commands/sflush.json
index bac27ad2d..b076e33d9 100644
--- a/src/commands/sflush.json
+++ b/src/commands/sflush.json
@@ -7,8 +7,7 @@
         "arity": -3,
         "function": "sflushCommand",
         "command_flags": [
-            "WRITE",
-            "EXPERIMENTAL"
+            "WRITE"
         ],
         "acl_categories": [
             "KEYSPACE",
diff --git a/tests/unit/cluster/multi-slot-operations.tcl b/tests/unit/cluster/multi-slot-operations.tcl
index 905fe676a..32eab0bc1 100644
--- a/tests/unit/cluster/multi-slot-operations.tcl
+++ b/tests/unit/cluster/multi-slot-operations.tcl
@@ -108,11 +108,85 @@ test "DELSLOTSRANGE command with several boundary conditions test suite" {
 }
 } cluster_allocate_with_continuous_slots_local
 
-start_cluster 2 0 {tags {external:skip cluster experimental}} {
+start_cluster 2 0 {tags {external:skip cluster}} {
 
 set master1 [srv 0 "client"]
 set master2 [srv -1 "client"]
 
+# Stream IDMP + cluster partial SFLUSH (multi slot ranges)
+# Covers streamMoveIdmpKeys() moving keys for all trimmed ranges in one pass.
+# Requires: cluster mode, background trim (default), partial SFLUSH (not full node flush).
+
+# Helper: find a key name whose hash tag lands on a given slot (0 - 16383).
+# Only the part inside {...} is hashed, so we bruteforce the tag text.
+proc stream_keys_for_slot {redis_cmd slot} {
+    for {set i 0} {$i < 100000} {incr i} {
+        set key "\{sidmp$i\}:s"
+        if {[$redis_cmd cluster keyslot $key] == $slot} {
+            return $key
+        }
+    }
+    error "could not build a key for slot $slot"
+}
+
+test {SFLUSH multiple ranges removes IDMP streams in those slots only} {
+    # clean state on this master (owns slots 0-8191)
+    $master1 FLUSHALL
+
+    # Use background trim (since we want to test asmTriggerBackgroundTrim())
+    $master1 debug asm-trim-method bg
+
+    # Three slots, all on node 0 (0-8191): two we will flush (slot_a and slot_b), one of it we will keep (slot_c)
+    set slot_a 100
+    set slot_b 5000
+    set slot_c 7000
+
+    set k_a [stream_keys_for_slot $master1 $slot_a]
+    set k_b [stream_keys_for_slot $master1 $slot_b]
+    set k_c [stream_keys_for_slot $master1 $slot_c]
+
+    # create streams with IDMP so they are tracked in dict stream_idmp_keys
+    $master1 XADD $k_a IDMP p1 "init" * field "init"
+    $master1 XADD $k_b IDMP p1 "init" * field "init"
+    $master1 XADD $k_c IDMP p1 "init" * field "init"
+
+    # Long duration so the cron does not clear IDMP state during the test
+    $master1 XCFGSET $k_a IDMP-DURATION 86400
+    $master1 XCFGSET $k_b IDMP-DURATION 86400
+    $master1 XCFGSET $k_c IDMP-DURATION 86400
+
+    # Real IDMP entries
+    set id_a [$master1 XADD $k_a IDMP p1 "req_a" * field v1]
+    set id_b [$master1 XADD $k_b IDMP p1 "req_b" * field v1]
+    set id_c [$master1 XADD $k_c IDMP p1 "req_c" * field v1]
+
+    assert_equal 1 [dict get [$master1 XINFO STREAM $k_a] pids-tracked]
+    assert_equal 1 [dict get [$master1 XINFO STREAM $k_b] pids-tracked]
+    assert_equal 1 [dict get [$master1 XINFO STREAM $k_c] pids-tracked]
+
+    # two disjoint ranges that include slot_a and slot_b but not slot_c
+    set lo_a [expr {$slot_a - 5}]
+    set hi_a [expr {$slot_a + 5}]
+    set lo_b [expr {$slot_b - 5}]
+    set hi_b [expr {$slot_b + 5}]
+
+    # partial SFLUSH: not the whole 0-8191, this is a real trim (not FLUSHDB shortcut)
+    $master1 SFLUSH $lo_a $hi_a $lo_b $hi_b SYNC
+
+    # Wait until two flushed streams are gone and third remains
+    wait_for_condition 1000 10 {
+        [$master1 EXISTS $k_a] == 0 && [$master1 EXISTS $k_b] == 0 && [$master1 EXISTS $k_c] == 1
+    } else {
+        fail "SFLUSH did not delete only the expected streams in time"
+    }
+
+    # remaining streams should still deduplicate IDMP correctly
+    assert_equal $id_c [$master1 XADD $k_c IDMP p1 "req_c" * field "dup"]
+
+    # sanity, we did not accidentally wipe the whole db
+    assert {[$master1 DBSIZE] >= 1}
+}
+
 test "SFLUSH - Errors and output validation" {
     assert_match "* 0-8191*" [$master1 CLUSTER NODES]
     assert_match "* 8192-16383*" [$master2 CLUSTER NODES]

From 396a28eabdf72d9a79455ec1c2cb9bb0e95ab297 Mon Sep 17 00:00:00 2001
From: Shubham Taple <subbutaple@gmail.com>
Date: Sat, 18 Apr 2026 16:58:26 +0530
Subject: [PATCH 3/5] Revert "Add test for asmTriggerBackgroundTrim, remove
 temporary EXPERIMENTAL tag from sflush.json and tcl"

This reverts commit f57ef334493a57ec4a7e1aa46c994a15e681308c.

Revert test using sflush
---
 src/commands.def                             | 36 ----------
 src/commands/sflush.json                     |  3 +-
 tests/unit/cluster/multi-slot-operations.tcl | 76 +-------------------
 3 files changed, 3 insertions(+), 112 deletions(-)

diff --git a/src/commands.def b/src/commands.def
index ecf5c7da6..3980365d4 100644
--- a/src/commands.def
+++ b/src/commands.def
@@ -8171,41 +8171,6 @@ struct COMMAND_ARG RESTORE_ASKING_Args[] = {
 #define SAVE_Keyspecs NULL
 #endif
 
-/********** SFLUSH ********************/
-
-#ifndef SKIP_CMD_HISTORY_TABLE
-/* SFLUSH history */
-#define SFLUSH_History NULL
-#endif
-
-#ifndef SKIP_CMD_TIPS_TABLE
-/* SFLUSH tips */
-#define SFLUSH_Tips NULL
-#endif
-
-#ifndef SKIP_CMD_KEY_SPECS_TABLE
-/* SFLUSH key specs */
-#define SFLUSH_Keyspecs NULL
-#endif
-
-/* SFLUSH data argument table */
-struct COMMAND_ARG SFLUSH_data_Subargs[] = {
-{MAKE_ARG("slot-start",ARG_TYPE_INTEGER,-1,NULL,NULL,NULL,CMD_ARG_NONE,0,NULL)},
-{MAKE_ARG("slot-last",ARG_TYPE_INTEGER,-1,NULL,NULL,NULL,CMD_ARG_NONE,0,NULL)},
-};
-
-/* SFLUSH flush_type argument table */
-struct COMMAND_ARG SFLUSH_flush_type_Subargs[] = {
-{MAKE_ARG("async",ARG_TYPE_PURE_TOKEN,-1,"ASYNC",NULL,NULL,CMD_ARG_NONE,0,NULL)},
-{MAKE_ARG("sync",ARG_TYPE_PURE_TOKEN,-1,"SYNC",NULL,NULL,CMD_ARG_NONE,0,NULL)},
-};
-
-/* SFLUSH argument table */
-struct COMMAND_ARG SFLUSH_Args[] = {
-{MAKE_ARG("data",ARG_TYPE_BLOCK,-1,NULL,NULL,NULL,CMD_ARG_MULTIPLE,2,NULL),.subargs=SFLUSH_data_Subargs},
-{MAKE_ARG("flush-type",ARG_TYPE_ONEOF,-1,NULL,NULL,NULL,CMD_ARG_OPTIONAL,2,NULL),.subargs=SFLUSH_flush_type_Subargs},
-};
-
 /********** SHUTDOWN ********************/
 
 #ifndef SKIP_CMD_HISTORY_TABLE
@@ -11945,7 +11910,6 @@ struct COMMAND_STRUCT redisCommandTable[] = {
 {MAKE_CMD("restore-asking","An internal command for migrating keys in a cluster.","O(1) to create the new key and additional O(N*M) to reconstruct the serialized value, where N is the number of Redis objects composing the value and M their average size. For small string values the time complexity is thus O(1)+O(1*M) where M is small, so simply O(1). However for sorted set values the complexity is O(N*M*log(N)) because inserting values into sorted sets is O(log(N)).","3.0.0",CMD_DOC_SYSCMD,NULL,NULL,"server",COMMAND_GROUP_SERVER,RESTORE_ASKING_History,3,RESTORE_ASKING_Tips,0,restoreCommand,-4,CMD_WRITE|CMD_DENYOOM|CMD_ASKING,ACL_CATEGORY_KEYSPACE|ACL_CATEGORY_DANGEROUS,RESTORE_ASKING_Keyspecs,1,NULL,7),.args=RESTORE_ASKING_Args},
 {MAKE_CMD("role","Returns the replication role.","O(1)","2.8.12",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,ROLE_History,0,ROLE_Tips,0,roleCommand,1,CMD_NOSCRIPT|CMD_LOADING|CMD_STALE|CMD_FAST|CMD_SENTINEL,ACL_CATEGORY_ADMIN|ACL_CATEGORY_DANGEROUS,ROLE_Keyspecs,0,NULL,0)},
 {MAKE_CMD("save","Synchronously saves the database(s) to disk.","O(N) where N is the total number of keys in all databases","1.0.0",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,SAVE_History,0,SAVE_Tips,0,saveCommand,1,CMD_NO_ASYNC_LOADING|CMD_ADMIN|CMD_NOSCRIPT|CMD_NO_MULTI,0,SAVE_Keyspecs,0,NULL,0)},
-{MAKE_CMD("sflush","Remove all keys from selected range of slots.","O(N)+O(k) where N is the number of keys and k is the number of slots.","8.0.0",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,SFLUSH_History,0,SFLUSH_Tips,0,sflushCommand,-3,CMD_WRITE,ACL_CATEGORY_KEYSPACE|ACL_CATEGORY_DANGEROUS,SFLUSH_Keyspecs,0,NULL,2),.args=SFLUSH_Args},
 {MAKE_CMD("shutdown","Synchronously saves the database(s) to disk and shuts down the Redis server.","O(N) when saving, where N is the total number of keys in all databases when saving data, otherwise O(1)","1.0.0",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,SHUTDOWN_History,1,SHUTDOWN_Tips,0,shutdownCommand,-1,CMD_ADMIN|CMD_NOSCRIPT|CMD_LOADING|CMD_STALE|CMD_NO_MULTI|CMD_SENTINEL|CMD_ALLOW_BUSY,0,SHUTDOWN_Keyspecs,0,NULL,4),.args=SHUTDOWN_Args},
 {MAKE_CMD("slaveof","Sets a Redis server as a replica of another, or promotes it to being a master.","O(1)","1.0.0",CMD_DOC_DEPRECATED,"`REPLICAOF`","5.0.0","server",COMMAND_GROUP_SERVER,SLAVEOF_History,0,SLAVEOF_Tips,0,replicaofCommand,3,CMD_NO_ASYNC_LOADING|CMD_ADMIN|CMD_NOSCRIPT|CMD_STALE,0,SLAVEOF_Keyspecs,0,NULL,1),.args=SLAVEOF_Args},
 {MAKE_CMD("slowlog","A container for slow log commands.","Depends on subcommand.","2.2.12",CMD_DOC_NONE,NULL,NULL,"server",COMMAND_GROUP_SERVER,SLOWLOG_History,0,SLOWLOG_Tips,0,NULL,-2,0,0,SLOWLOG_Keyspecs,0,NULL,0),.subcommands=SLOWLOG_Subcommands},
diff --git a/src/commands/sflush.json b/src/commands/sflush.json
index b076e33d9..bac27ad2d 100644
--- a/src/commands/sflush.json
+++ b/src/commands/sflush.json
@@ -7,7 +7,8 @@
         "arity": -3,
         "function": "sflushCommand",
         "command_flags": [
-            "WRITE"
+            "WRITE",
+            "EXPERIMENTAL"
         ],
         "acl_categories": [
             "KEYSPACE",
diff --git a/tests/unit/cluster/multi-slot-operations.tcl b/tests/unit/cluster/multi-slot-operations.tcl
index 32eab0bc1..905fe676a 100644
--- a/tests/unit/cluster/multi-slot-operations.tcl
+++ b/tests/unit/cluster/multi-slot-operations.tcl
@@ -108,85 +108,11 @@ test "DELSLOTSRANGE command with several boundary conditions test suite" {
 }
 } cluster_allocate_with_continuous_slots_local
 
-start_cluster 2 0 {tags {external:skip cluster}} {
+start_cluster 2 0 {tags {external:skip cluster experimental}} {
 
 set master1 [srv 0 "client"]
 set master2 [srv -1 "client"]
 
-# Stream IDMP + cluster partial SFLUSH (multi slot ranges)
-# Covers streamMoveIdmpKeys() moving keys for all trimmed ranges in one pass.
-# Requires: cluster mode, background trim (default), partial SFLUSH (not full node flush).
-
-# Helper: find a key name whose hash tag lands on a given slot (0 - 16383).
-# Only the part inside {...} is hashed, so we bruteforce the tag text.
-proc stream_keys_for_slot {redis_cmd slot} {
-    for {set i 0} {$i < 100000} {incr i} {
-        set key "\{sidmp$i\}:s"
-        if {[$redis_cmd cluster keyslot $key] == $slot} {
-            return $key
-        }
-    }
-    error "could not build a key for slot $slot"
-}
-
-test {SFLUSH multiple ranges removes IDMP streams in those slots only} {
-    # clean state on this master (owns slots 0-8191)
-    $master1 FLUSHALL
-
-    # Use background trim (since we want to test asmTriggerBackgroundTrim())
-    $master1 debug asm-trim-method bg
-
-    # Three slots, all on node 0 (0-8191): two we will flush (slot_a and slot_b), one of it we will keep (slot_c)
-    set slot_a 100
-    set slot_b 5000
-    set slot_c 7000
-
-    set k_a [stream_keys_for_slot $master1 $slot_a]
-    set k_b [stream_keys_for_slot $master1 $slot_b]
-    set k_c [stream_keys_for_slot $master1 $slot_c]
-
-    # create streams with IDMP so they are tracked in dict stream_idmp_keys
-    $master1 XADD $k_a IDMP p1 "init" * field "init"
-    $master1 XADD $k_b IDMP p1 "init" * field "init"
-    $master1 XADD $k_c IDMP p1 "init" * field "init"
-
-    # Long duration so the cron does not clear IDMP state during the test
-    $master1 XCFGSET $k_a IDMP-DURATION 86400
-    $master1 XCFGSET $k_b IDMP-DURATION 86400
-    $master1 XCFGSET $k_c IDMP-DURATION 86400
-
-    # Real IDMP entries
-    set id_a [$master1 XADD $k_a IDMP p1 "req_a" * field v1]
-    set id_b [$master1 XADD $k_b IDMP p1 "req_b" * field v1]
-    set id_c [$master1 XADD $k_c IDMP p1 "req_c" * field v1]
-
-    assert_equal 1 [dict get [$master1 XINFO STREAM $k_a] pids-tracked]
-    assert_equal 1 [dict get [$master1 XINFO STREAM $k_b] pids-tracked]
-    assert_equal 1 [dict get [$master1 XINFO STREAM $k_c] pids-tracked]
-
-    # two disjoint ranges that include slot_a and slot_b but not slot_c
-    set lo_a [expr {$slot_a - 5}]
-    set hi_a [expr {$slot_a + 5}]
-    set lo_b [expr {$slot_b - 5}]
-    set hi_b [expr {$slot_b + 5}]
-
-    # partial SFLUSH: not the whole 0-8191, this is a real trim (not FLUSHDB shortcut)
-    $master1 SFLUSH $lo_a $hi_a $lo_b $hi_b SYNC
-
-    # Wait until two flushed streams are gone and third remains
-    wait_for_condition 1000 10 {
-        [$master1 EXISTS $k_a] == 0 && [$master1 EXISTS $k_b] == 0 && [$master1 EXISTS $k_c] == 1
-    } else {
-        fail "SFLUSH did not delete only the expected streams in time"
-    }
-
-    # remaining streams should still deduplicate IDMP correctly
-    assert_equal $id_c [$master1 XADD $k_c IDMP p1 "req_c" * field "dup"]
-
-    # sanity, we did not accidentally wipe the whole db
-    assert {[$master1 DBSIZE] >= 1}
-}
-
 test "SFLUSH - Errors and output validation" {
     assert_match "* 0-8191*" [$master1 CLUSTER NODES]
     assert_match "* 8192-16383*" [$master2 CLUSTER NODES]

From 23c513770d5fa5ee6b95743f9b33038a029bcd80 Mon Sep 17 00:00:00 2001
From: Shubham Taple <subbutaple@gmail.com>
Date: Sat, 18 Apr 2026 20:37:53 +0530
Subject: [PATCH 4/5] Add tests for bgtrim IDMP

---
 tests/unit/cluster/atomic-slot-migration.tcl | 117 +++++++++++++++++++
 1 file changed, 117 insertions(+)

diff --git a/tests/unit/cluster/atomic-slot-migration.tcl b/tests/unit/cluster/atomic-slot-migration.tcl
index 826f0d69c..64c5c5310 100644
--- a/tests/unit/cluster/atomic-slot-migration.tcl
+++ b/tests/unit/cluster/atomic-slot-migration.tcl
@@ -1696,6 +1696,123 @@ start_cluster 3 3 {tags {external:skip cluster} overrides {cluster-node-timeout
         R 0 debug asm-trim-method default
     }
 
+    test {Test bgtrim IDMP: disjoint ranges with in-range gap + far-slot; dedup on dest and source} {
+        # One IMPORT with two non-adjacent slot ranges (union trim). Slot between the ranges and a
+        # far slot stay on the source; migrated keys move to the dest. Exercises slotRangeArray
+        # membership + IDMP correctness (stream_idmp_keys vs one bg trim batch).
+        R 0 debug asm-trim-method bg
+        R 0 flushall
+
+        set k0 [slot_key 0 idmp]
+        set k1 [slot_key 1 idmp]
+        set k2 [slot_key 2 idmp]
+        set k4 [slot_key 4 idmp]
+        set k5 [slot_key 5 idmp]
+        set k6 [slot_key 6 idmp]
+        set k101 [slot_key 101 idmp]
+
+        foreach k [list $k0 $k1 $k2 $k4 $k5 $k6 $k101] {
+            R 0 XADD $k IDMP p1 "init" * field "init"
+            R 0 XCFGSET $k IDMP-DURATION 86400
+        }
+
+        set id0 [R 0 XADD $k0 IDMP p1 "r0" * field v0]
+        set id1 [R 0 XADD $k1 IDMP p1 "r1" * field v1]
+        set id2 [R 0 XADD $k2 IDMP p1 "r2" * field v2]
+        set id4 [R 0 XADD $k4 IDMP p1 "r4" * field v4]
+        set id5 [R 0 XADD $k5 IDMP p1 "r5" * field v5]
+        set id6 [R 0 XADD $k6 IDMP p1 "r6" * field v6]
+        set id101 [R 0 XADD $k101 IDMP p1 "r101" * field v101]
+
+        foreach k [list $k0 $k1 $k2 $k4 $k5 $k6 $k101] {
+            assert_equal 1 [dict get [R 0 XINFO STREAM $k] pids-tracked]
+        }
+
+        # Migrate [0-2] and [5-6] in a single IMPORT; slot 4 and 101 are outside both ranges.
+        # After migration, trimmed slots are owned by node 1: use R 1 for those keys (R 0 replies MOVED).
+        R 1 CLUSTER MIGRATION IMPORT 0 2 5 6
+        wait_for_asm_done
+
+        wait_for_condition 1000 10 {
+            [R 1 EXISTS $k0] == 1 && [R 1 EXISTS $k1] == 1 && [R 1 EXISTS $k2] == 1 &&
+            [R 1 EXISTS $k5] == 1 && [R 1 EXISTS $k6] == 1 &&
+            [R 0 EXISTS $k4] == 1 && [R 0 EXISTS $k101] == 1
+        } else {
+            fail "Migrated streams missing on destination or survivors missing on source"
+        }
+
+        foreach k [list $k0 $k1 $k2 $k5 $k6] {
+            assert_equal 1 [dict get [R 1 XINFO STREAM $k] pids-tracked]
+        }
+        assert_equal $id0 [R 1 XADD $k0 IDMP p1 "r0" * field dup]
+        assert_equal $id1 [R 1 XADD $k1 IDMP p1 "r1" * field dup]
+        assert_equal $id2 [R 1 XADD $k2 IDMP p1 "r2" * field dup]
+        assert_equal $id5 [R 1 XADD $k5 IDMP p1 "r5" * field dup]
+        assert_equal $id6 [R 1 XADD $k6 IDMP p1 "r6" * field dup]
+
+        assert_equal 1 [dict get [R 0 XINFO STREAM $k4] pids-tracked]
+        assert_equal 1 [dict get [R 0 XINFO STREAM $k101] pids-tracked]
+        assert_equal $id4 [R 0 XADD $k4 IDMP p1 "r4" * field dup]
+        assert_equal $id101 [R 0 XADD $k101 IDMP p1 "r101" * field dup]
+
+        # cleanup
+        wait_for_asm_done
+        R 0 CLUSTER MIGRATION IMPORT 0 2 5 6
+        wait_for_asm_done
+        R 0 flushall
+        R 0 debug asm-trim-method default
+    }
+
+    test {Test bgtrim IDMP: many streams; outer ranges migrated, inner + high slots kept} {
+        # Many IDMP entries across the shard; only outer slot ranges migrate so most keys stay on
+        # the source — selective trim vs a large stream_idmp_keys dict (same multi-range ASM path).
+        R 0 debug asm-trim-method bg
+        R 0 flushall
+
+        set keys {}
+        foreach slot {0 1 2 3 4 5 6 7 101 102 103} {
+            lappend keys [slot_key $slot idmp]
+        }
+
+        foreach k $keys {
+            R 0 XADD $k IDMP p1 "init" * field "init"
+            R 0 XCFGSET $k IDMP-DURATION 86400
+            R 0 XADD $k IDMP p1 "req" * field v1
+            assert_equal 1 [dict get [R 0 XINFO STREAM $k] pids-tracked]
+        }
+
+        # Single IMPORT: ranges [0-1] and [6-7]; slots 2-5 and 101-103 are not trimmed on source.
+        R 1 CLUSTER MIGRATION IMPORT 0 1 6 7
+        wait_for_asm_done
+
+        set kept_slots {2 3 4 5 101 102 103}
+        # Trimmed slots are served by node 1 after migration; survivors stay on node 0.
+        # wait_for_condition body must be a single expr (no foreach/set).
+        wait_for_condition 1000 10 {
+            [R 1 EXISTS [slot_key 0 idmp]] == 1 && [R 1 EXISTS [slot_key 1 idmp]] == 1 &&
+            [R 1 EXISTS [slot_key 6 idmp]] == 1 && [R 1 EXISTS [slot_key 7 idmp]] == 1 &&
+            [R 0 EXISTS [slot_key 2 idmp]] == 1 && [R 0 EXISTS [slot_key 3 idmp]] == 1 &&
+            [R 0 EXISTS [slot_key 4 idmp]] == 1 && [R 0 EXISTS [slot_key 5 idmp]] == 1 &&
+            [R 0 EXISTS [slot_key 101 idmp]] == 1 && [R 0 EXISTS [slot_key 102 idmp]] == 1 &&
+            [R 0 EXISTS [slot_key 103 idmp]] == 1
+        } else {
+            fail "Selective IDMP trim did not match migrated slot ranges"
+        }
+
+        foreach slot $kept_slots {
+            set k [slot_key $slot idmp]
+            assert_equal 1 [dict get [R 0 XINFO STREAM $k] pids-tracked]
+            R 0 XADD $k IDMP p1 "after_trim" * field x
+        }
+
+        # cleanup
+        wait_for_asm_done
+        R 0 CLUSTER MIGRATION IMPORT 0 1 6 7
+        wait_for_asm_done
+        R 0 flushall
+        R 0 debug asm-trim-method default
+    }
+
     test "Test bgtrim after a FAILOVER on destination side" {
         R 1 debug asm-trim-method bg
         R 4 debug asm-trim-method bg

From 2cd117bb9b47c265da9f1fbae4e06dda63bfe34b Mon Sep 17 00:00:00 2001
From: Shubham Taple <subbutaple@gmail.com>
Date: Sat, 25 Apr 2026 09:18:08 +0530
Subject: [PATCH 5/5] Use dictAddRaw since we have dict with no_value

---
 src/db.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/db.c b/src/db.c
index acb0cf788..869e8fc75 100644
--- a/src/db.c
+++ b/src/db.c
@@ -1121,7 +1121,7 @@ void streamMoveIdmpKeys(dict *src, dict *dst, slotRangeArray *slots) {
         /* Check if key belongs to the slot range. */
         if (!slotRangeArrayContains(slots, keyHashSlot(key->ptr, sdslen(key->ptr))))
             continue;
-        if (dictAdd(dst, key, dictGetVal(de)) == DICT_OK) {
+        if (dictAddRaw(dst, key, NULL)) {
             incrRefCount(key);
         }
         dictDelete(src, key);