On Wed, Mar 16, 2016 at 1:33 PM, Andres Freund <and...@anarazel.de> wrote: > On 2016-03-16 13:29:22 -0400, Robert Haas wrote: >> Whoa. At 64 clients, we're hardly getting any benefit, but then by 88 >> clients, we're getting a huge benefit. I wonder why there's that sharp >> change there. > > What's the specifics of the machine tested? I wonder if it either > correlates with the number of hardware threads, real cores, or cache > sizes.
I think this was done on cthulhu, whose /proc/cpuinfo output ends this way: processor : 127 vendor_id : GenuineIntel cpu family : 6 model : 47 model name : Intel(R) Xeon(R) CPU E7- 8830 @ 2.13GHz stepping : 2 microcode : 0x37 cpu MHz : 2129.000 cache size : 24576 KB physical id : 3 siblings : 16 core id : 25 cpu cores : 8 apicid : 243 initial apicid : 243 fpu : yes fpu_exception : yes cpuid level : 11 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic popcnt aes lahf_lm ida arat epb dtherm tpr_shadow vnmi flexpriority ept vpid bogomips : 4266.62 clflush size : 64 cache_alignment : 64 address sizes : 44 bits physical, 48 bits virtual power management: -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
