Random add/set errors on Debian/Memcached 1.1.12

[Mauro Maggi]

On Thu, 2007-12-06 at 19:18 -0800, dormando wrote:

> I'm willing to bet your pecl/memcache client could use an upgrade; I've 
> seen a lot of reports of this issue happening with the older client.
> 
> Also, 1.1.12 is fairly old and has _some_ bugs... I wouldn't be quick to 
> blame it on your issue though.

Our sysadmins are working on some upgrades on both the daemon and the
pecl/memcache client, as soon as the upgrades are up I'll post some
feedback

> 
> Otherwise, you should strace a process that's exhibiting issues and see 
> what the actual traffic between memcached and your client process looks 
> like. You can pull the real errors from that, send to the list, and 
> we'll work from there.



> 
> -Dormando
> 
> Mauro Maggi wrote:
> > We got some random errors with Memcached 1.1.12 on a (32-bit) production
> > server running Debian 4.0r1. The client API is the one provided with php
> > 4.4.4
> > 
> > memcache_set() and memcache_add() randomly fail when trying to set large
> > values ( > 30kb); the larger the entry length, the larger the number of
> > failures. Moreover, we get random notices like this one: 
> > "Notice: memcache_get_stats() [function.memcache-get-stats]: Server
> > 192.168.0.13 (tcp 11211) failed with: Failed reading line from stream
> > (0) in /path/to/script.php"
> > 
> > The same setup on a local developing box, with the same setup, gives us
> > no failures and everything works ok.
> > 
> > What's wrong in our production box? Is there a way to get an insight on
> > why the functions are failing, other than their "false" return value?
> > 
> > What follows is the phpinfo() memcached reported configuration and the output of the memcache_get_advanced_server_stats on our production box:
> > 
> > Revision 	$Revision: 1.92 $
> > memcache.allow_failover	1
> > memcache.chunk_size	8192
> > memcache.default_port	11211
> > memcache.hash_function	crc32
> > memcache.hash_strategy	standard
> > memcache.max_failover_attempts	20
> > 
> > ----
> > 
> > Server stats:array(19) {
> >   ["pid"]=>
> >   string(4) "2735"
> >   ["uptime"]=>
> >   string(6) "355498"
> >   ["time"]=>
> >   string(10) "1196778820"
> >   ["version"]=>
> >   string(6) "1.1.12"
> >   ["rusage_user"]=>
> >   string(10) "230.270391"
> >   ["rusage_system"]=>
> >   string(10) "452.140257"
> >   ["curr_items"]=>
> >   string(7) "1012241"
> >   ["total_items"]=>
> >   string(8) "10852467"
> >   ["bytes"]=>
> >   string(10) "1429072369"
> >   ["curr_connections"]=>
> >   string(3) "469"
> >   ["total_connections"]=>
> >   string(7) "6798948"
> >   ["connection_structures"]=>
> >   string(3) "654"
> >   ["cmd_get"]=>
> >   string(8) "10898327"
> >   ["cmd_set"]=>
> >   string(8) "10852467"
> >   ["get_hits"]=>
> >   string(7) "8061893"
> >   ["get_misses"]=>
> >   string(7) "2836434"
> >   ["bytes_read"]=>
> >   string(11) "18236447981"
> >   ["bytes_written"]=>
> >   string(11) "14350735133"
> >   ["limit_maxbytes"]=>
> >   string(10) "2147483648"
> > }
> > 
> > 
> > 
>