flock(fd, LOCK_UN) taking 500ms+ ?

John Levon (levon@movementarian.org)
Wed, 2 Oct 2002 03:39:01 +0100


In 2.5.40, our application is getting seemingly very large
flock(LOCK_UN) latencies :

Unlock, took 541386 usecs
Old was 567999237 secs, 131042 usecs
now is 567999237 secs, 672428 usecs
Unlock, took 125083 usecs
Old was 567999237 secs, 699310 usecs
now is 567999237 secs, 824393 usecs
Unlock, took 151245 usecs
Old was 567999237 secs, 825119 usecs
now is 567999237 secs, 976364 usecs

(using gettimeofday ...)

No similar times are observed during the corresponding LOCK_EX call.

Is this just a silly app bug somewhere, or something funny in locks.c ?

More details, testing etc. on request ...

regards
john

-- 
"I never understood what's so hard about picking a unique
 first and last name - and not going beyond the 6 character limit."
 	- Toon Moene
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/