From d3701d27141b8e400ccdf5fbf22c504d112fab63 Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Sat, 21 Apr 2012 19:20:03 +0200
Subject: [PATCH] Limit memory used by big SLOWLOG entries.
Two limits are added:
1) Up to SLOWLOG_ENTRY_MAX_ARGV arguments are logged.
2) Up to SLOWLOG_ENTRY_MAX_STRING bytes per argument are logged.
3) slowlog-max-len is set to 128 by default (was 1024).
The number of remaining arguments / bytes is logged in the entry
so that the user can understand better the nature of the logged command.
---
redis.conf | 2 +-
src/redis.h | 2 +-
src/slowlog.c | 35 +++++++++++++++++++++++++++++------
src/slowlog.h | 3 +++
tests/unit/slowlog.tcl | 17 +++++++++++++++++
5 files changed, 51 insertions(+), 8 deletions(-)
diff --git a/redis.conf b/redis.conf
index b1ea6c2e..ed0e2f0e 100644
--- a/redis.conf
+++ b/redis.conf
@@ -447,7 +447,7 @@ slowlog-log-slower-than 10000
# There is no limit to this length. Just be aware that it will consume memory.
# You can reclaim memory used by the slow log with SLOWLOG RESET.
-slowlog-max-len 1024
+slowlog-max-len 128
############################### ADVANCED CONFIG ###############################
diff --git a/src/redis.h b/src/redis.h
index 42a9b581..3b9d4e78 100644
--- a/src/redis.h
+++ b/src/redis.h
@@ -52,7 +52,7 @@
#define REDIS_AOF_REWRITE_MIN_SIZE (1024*1024)
#define REDIS_AOF_REWRITE_ITEMS_PER_CMD 64
#define REDIS_SLOWLOG_LOG_SLOWER_THAN 10000
-#define REDIS_SLOWLOG_MAX_LEN 64
+#define REDIS_SLOWLOG_MAX_LEN 128
#define REDIS_MAX_CLIENTS 10000
#define REDIS_REPL_TIMEOUT 60
diff --git a/src/slowlog.c b/src/slowlog.c
index cfd66dc6..53c44a01 100644
--- a/src/slowlog.c
+++ b/src/slowlog.c
@@ -16,13 +16,36 @@
* this function. */
slowlogEntry *slowlogCreateEntry(robj **argv, int argc, long long duration) {
slowlogEntry *se = zmalloc(sizeof(*se));
- int j;
+ int j, slargc = argc;
+
+ if (slargc > SLOWLOG_ENTRY_MAX_ARGC) slargc = SLOWLOG_ENTRY_MAX_ARGC;
+ se->argc = slargc;
+ se->argv = zmalloc(sizeof(robj*)*slargc);
+ for (j = 0; j < slargc; j++) {
+ /* Logging too many arguments is a useless memory waste, so we stop
+ * at SLOWLOG_ENTRY_MAX_ARGC, but use the last argument to specify
+ * how many remaining arguments there were in the original command. */
+ if (slargc != argc && j == slargc-1) {
+ se->argv[j] = createObject(REDIS_STRING,
+ sdscatprintf(sdsempty(),"... (%d more arguments)",
+ argc-slargc+1));
+ } else {
+ /* Trim too long strings as well... */
+ if (argv[j]->type == REDIS_STRING &&
+ argv[j]->encoding == REDIS_ENCODING_RAW &&
+ sdslen(argv[j]->ptr) > SLOWLOG_ENTRY_MAX_STRING)
+ {
+ sds s = sdsnewlen(argv[j]->ptr, SLOWLOG_ENTRY_MAX_STRING);
- se->argc = argc;
- se->argv = zmalloc(sizeof(robj*)*argc);
- for (j = 0; j < argc; j++) {
- se->argv[j] = argv[j];
- incrRefCount(argv[j]);
+ s = sdscatprintf(s,"... (%lu more bytes)",
+ (unsigned long)
+ sdslen(argv[j]->ptr) - SLOWLOG_ENTRY_MAX_STRING);
+ se->argv[j] = createObject(REDIS_STRING,s);
+ } else {
+ se->argv[j] = argv[j];
+ incrRefCount(argv[j]);
+ }
+ }
}
se->time = time(NULL);
se->duration = duration;
diff --git a/src/slowlog.h b/src/slowlog.h
index bad770db..bcc961cc 100644
--- a/src/slowlog.h
+++ b/src/slowlog.h
@@ -1,3 +1,6 @@
+#define SLOWLOG_ENTRY_MAX_ARGC 32
+#define SLOWLOG_ENTRY_MAX_STRING 128
+
/* This structure defines an entry inside the slow log list */
typedef struct slowlogEntry {
robj **argv;
diff --git a/tests/unit/slowlog.tcl b/tests/unit/slowlog.tcl
index 55a71e98..2216e925 100644
--- a/tests/unit/slowlog.tcl
+++ b/tests/unit/slowlog.tcl
@@ -38,4 +38,21 @@ start_server {tags {"slowlog"} overrides {slowlog-log-slower-than 1000000}} {
assert_equal [expr {[lindex $e 2] > 100000}] 1
assert_equal [lindex $e 3] {debug sleep 0.2}
}
+
+ test {SLOWLOG - commands with too many arguments are trimmed} {
+ r config set slowlog-log-slower-than 0
+ r slowlog reset
+ r sadd set 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
+ set e [lindex [r slowlog get] 0]
+ lindex $e 3
+ } {sadd set 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 {... (2 more arguments)}}
+
+ test {SLOWLOG - too long arguments are trimmed} {
+ r config set slowlog-log-slower-than 0
+ r slowlog reset
+ set arg [string repeat A 129]
+ r sadd set foo $arg
+ set e [lindex [r slowlog get] 0]
+ lindex $e 3
+ } {sadd set foo {AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA... (1 more bytes)}}
}
--
2.47.2