On Thu, Aug 30, 2012 at 1:25 PM, Peter Geoghegan <pe...@2ndquadrant.com> wrote:
> Just how helpful is effective_io_concurrency? Did someone produce a > benchmark at some point? Attached is a benchmark I put together a while ago. I don't know how close to "real world" it might be. I haven't seen it in the wild, but I'm anticipating I will see something like it soon. The benefit is of course reduced if you were to apply high levels of -c $clients, but cases where -c 1 are frequent in data mining and such. Obviously it would be better to cluster the giant table on "abalance", but that might be hard to do and then hard to maintain. Size of generated database is about 70GB. Server had 16GB of RAM. It is a virtual server, and I don't know the real hardware, but am told it has 8 spindles. (if the range used in the query is increased from +100 to +1000, even more speed up is available) effective_io_concurrency tps 0 2.06273064 1 2.1693092 2 4.11726948 3 5.90785352 4 6.65748384 5 7.58297556 6 8.36130404 7 8.86561116 8 9.2673546 9 9.57076168 10 9.8558758 11 10.11641752 12 10.316673 13 10.46953468 14 10.65962516 15 10.76328636 16 10.86442376 17 10.96362168 18 11.04371008 19 11.19470171 20 11.30110867 21 11.39553967 22 11.45420263 23 11.54764725 24 11.61949146 25 11.65659225 26 11.68992392 27 11.75944667 28 11.7456135 29 11.80111779 30 11.72897188 31 11.7210945 32 11.73292504 33 11.734458 34 11.75195196 35 11.79079175 36 11.73687979 37 11.79583758 38 11.75879063 39 11.77868596 40 11.74685896 41 11.76294508 42 11.7213265 43 11.68458158 44 11.71036729 45 11.72728229 46 11.72063796 47 11.80322429 48 11.83563058 49 11.81916996 50 11.73395892 Cheers, Jeff
bitmap.sql
Description: Binary data
bench.sh
Description: Bourne shell script
setup.sql
Description: Binary data
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