That¹s just the thing. Even the initial queries have similar response times as the later ones. WEIRD!
I was considering running from /dev/shm in production, but for slaves only (master remains on disk). At this point though, I'm not seeing a benefit to ramdisk so I think I'm going back to traditional disk so the indexes stay intact after a power cycle. Has anyone else seen that indexes served from disk perform similarly as indexes served from ramdisk? -Park On 6/2/11 4:15 PM, "Erick Erickson" <erickerick...@gmail.com> wrote: >What I expect is happening is that the Solr caches are effectively making >the >two tests identical, using memory to hold the vital parts of the code in >both >cases (after disk warming on the instance using the local disk). I >suspect if >you measured the first few queries (assuming no auto-warming) you'd see >the >local disk version be slower. > >Were you running these tests for curiosity or is running from /dev/shm >something >you're considering for production? > >Best >Erick > >On Thu, Jun 2, 2011 at 5:47 PM, Parker Johnson <parker_john...@gap.com> >wrote: >> >> Hey everyone. >> >> Been doing some load testing over the past few days. I've been throwing >>a >> good bit of load at an instance of solr and have been measuring response >> time. We're running a variety of different keyword searches to keep >> solr's cache on its toes. >> >> I'm running two exact same load testing scenarios: one with indexes >> residing in /dev/shm and another from local disk. The indexes are about >> 4.5GB in size. >> >> On both tests the response times are the same. I wasn't expecting that. >> I do see the java heap size grow when indexes are served from disk >>(which >> is expected). When the indexes are served out of /dev/shm, the java >>heap >> stays small. >> >> So in general is this consistent behavior? I don't really see the >> advantage of serving indexes from /dev/shm. When the indexes are being >> served out of ramdisk, is the linux kernel or the memory mapper doing >> something tricky behind the scenes to use ramdisk in lieu of the java >>heap? >> >> For what it is worth, we are running x_64 rh5.4 on a 12 core 2.27Ghz >>Xeon >> system with 48GB ram. >> >> Thoughts? >> >> -Park >> >> >> >
