FYI for those of you tracking Linux development kernel performance on PostgreSQL.
-----Forwarded Message----- From: Mary Edie Meredith <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: DBT3-pgsql large performance improvement 2.6.6-rc1 Date: Fri, 16 Apr 2004 09:51:47 -0700 Performance in DBT-3 (using PostgreSQL) has vastly improved for _both in the "power" portion (single process/query) and in the "throughput" portion of the test (when the test is running multiple processes) on our 4-way(4GB) and 8-way(8GB) STP systems as compared 2.6.5 kernel results. Using the default DBT-3 options (ie using LVM, ext2, PostgreSQL version 7.4.1) Note: Bigger numbers are better. Kernel....Runid..CPUs.Power..%incP.Thruput %incT 2.6.5 291308 4 97.08 base 120.46 base 2.6.6-rc1 291876 4 146.11 50.5% 222.94 85.1% Kernel....Runid..CPUs.Power..%incP..Thruput %incT 2.6.5 291346 8 101.08 base 138.95 base 2.6.6-rc1 291915 8 151.69 50.1% 273.69 97.0% So the improvement is between 50% and 97%! Profile 2.6.5 8way throughput phase: http://khack.osdl.org/stp/291346/profile/after_throughput_test_1-tick.sort Profile 2.6.6-r1 8way throughput phase: http://khack.osdl.org/stp/291915/profile/after_throughput_test_1-tick.sort What I notice is that radix_tree_lookup is in the top 20 in the 2.6.5 profile, but not in 2.6.6-rc1. Could the radix tree changes be responsible for this? DBT-3 is a read mostly DSS workload and the throughput phase is where we run multiple query streams (as many as we have CPUs). In this workload, the database is stored on a file system, but it is small relative to the amount of memory (4GB and 8GB). It almost completely caches in page cache early on. So there is some physical IO in the first few minutes, but very little to none in the remainder. -- Mary Edie Meredith [EMAIL PROTECTED] 503-626-2455 x42 Open Source Development Labs ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html
