Actually sorry I should've been more descriptive. I plan on using a java client to get the stats from memcached so that we can eventually pipe the stats to our monitoring software. What would be the best java client? Spymemcached?
Also, is there any consideration in the future to provide stats via JMX? -ts -----Original Message----- From: memcached@googlegroups.com [mailto:memcac...@googlegroups.com] On Behalf Of dormando Sent: Tuesday, May 18, 2010 1:58 AM To: memcached@googlegroups.com Subject: RE: Global Lock When Getting Stats? memcached.org/wiki also inside the source tarball there's a "protocol.txt" that explains the raw stats thoroughly. You seem to be referring to the php api's stats call. On Mon, 17 May 2010, Tim Sneed wrote: > Great thanks for the information! Is there any documentation available from > the project team that explains the monitoring aspects of memcached? Such as > the methods of receiving stats (if there are any aside from getStats())? > > > -----Original Message----- > From: memcached@googlegroups.com [mailto:memcac...@googlegroups.com] On > Behalf Of dormando > Sent: Thursday, May 13, 2010 4:57 PM > To: memcached > Subject: Re: Global Lock When Getting Stats? > > > I was watching a Memcached video spoken by John Adams when I heard > > something that made me curious. When one gets stats from memcached, > > does it really perform a global lock? Does anyone have any good test > > cases on what sort of impact there is with an increasing node size > > with respect to performance degradation? > > 'stats sizes' grabs a global lock and iterates the whole cache. we don't > recommend you run that one. All other stats commands are extremely fast. > > > I am looking to do some research on expanding our product to support > > real-time monitoring, management, and analysis of memcached. But I'm a > > little concerned that this lock occurs during every stat collection, > > so much to the point that John Adams mentions that it can noticeably > > degrade the performance of memcached. I tried to do some research on > > my own but am finding very little performance analysis or any > > benchmark info with respect to constant polling (minimally 30 sec > > interval) of a enterprise-level memcached distributed system. Has > > anyone seen bad performance with respect to a large cluster and > > gathering stats? Any info would be great, thanks! > > There is no major lock every stat collection. There's a minor lock and > reading the values is very fast. > > A while ago twitter was running an extremely old version of memcached and > they took a long time to upgrade. That particular version had a bug in > stats collection that was *missing* a mutex lock, and would thus crash > sometimes. So they were afraid of running stats commands. That bug hasn't > existed for three years at least. > > -Dormando > >
