On Thursday 10 May 2007 17:57, Paul Winkler wrote:
On Thu, May 10, 2007 at 02:10:40AM +0200, Gaute Amundsen wrote:
On Wednesday 09 May 2007 16:41, Paul Winkler wrote:
On Wed, May 09, 2007 at 12:07:54PM +0200, Gaute Amundsen wrote:
So there is no other possible limit in a zope instance than IO or CPU?
Well, there's RAM of course. If you run out and start swapping a lot, that's a big problem :)
About 12G in that box, so that's unlikely.
btw, if you haven't come across this yet, I recommend reading Chris McDonough's "Scaling Zope" presentation. It's a couple years old but still a very good place to start: http://www.plope.org/misc/szweb/img0.html
Looks good. Thanks :-)
Something out of Control_Panel/Database/main/manage_activity perhaps?
Very helpful if the trouble is ZODB I/O. Have a look at the activity graph and see if you're getting lots of loads... might mean your ZODB cache is too small and is getting thrashed.
I set cache-size to 10000 last night, up from the default. I felt I had to try that before I had a grap in place, so I don't have good numbers to estimate tha change, but with about 20 hits a sec on apache, there was close to 500000 loads the last hour, and just 3000 writes. Does that look reasonable? The built in help seems to indicate I should increase the cache until reads approaches zero..?
Also, I don't think you've mentioned what sort of app this is. Is it mostly reads or are there lots of writes? "Mostly reads" is a lot easier to optimize :)
Big CMS system with about 70 virtual domains.
Is there a way to get that data out without going through port 8080?
Don't think so. But I've never looked.
Hm. I guess if I at least use a url on the management port, it ought to stay available when everything else bogs down.
Maybe I wil start logging the responstime directly like that! Hm.. good idea :)
If you need that, the trace log can also tell you exactly what the response time per request is.
Good for debugging, but for permanent use, I wil use this: http://muninexchange.projects.linpro.no/?search&cid=10&pid=61&phid=81
- DeadlockDebugger may be informative. http://www.zope.org/Members/nuxeo/Products/DeadlockDebugger
Sounds a little drastic on a production server, but it may stil come to that.. Ought to test it out on another server I guess.
Definitely test-drive it on a scratch server, but production is where you really need it :-)
re. trace log:
That looks interesting, except that it can take 15 minutes or more to restart zope when load is at the worst. I could try it outside of peak ours I guess.
Yeah, restart during off hours and leave it enabled until you have one episode of peak load slowdown.
Gaute.