On Thu, 04 Dec 2025 14:06:40 -0500 Tom Lane <[email protected]> wrote:
Hi Tom, > > Yeah. Check out the ratings at > > https://browser.geekbench.com > I guess these ratings will come handy to help pick my next server, thank you. >They seem to think the i5-5300U is a 2-core device, maybe you are counting >hyperthreading? 'cat /proc/cpuinfo' lists 4 processors (0 to 3), which I assumed to be cores, but my knowledge about hardware is very limited, so I may be misinterpreting (pasted it at the bottom of this message) > So from these numbers I'd ask not "why 3x slower?" but "why only > 3x slower?". Maybe your queries are partly disk-bound. Not sure how I can check this, but here is the plan for the same query, ran on an HDD with the same configuration as the others. It incurs a 30% performance penalty, compared to the bad SDD. This machine is a kimsufi dedicated server, advertised as KS-3 - Atom N2800 - 4GB DDR3 1066 MHz although cpuinfo tells me : model name : Intel(R) Atom(TM) CPU N2800 @ 1.86GHz QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Sort (cost=4534.02..4535.23 rows=485 width=458) (actual time=1237.451..1237.695 rows=1000 loops=1) Sort Key: t1.row_number Sort Method: quicksort Memory: 384kB -> Hash Join (cost=3002.19..4512.38 rows=485 width=458) (actual time=860.457..1232.407 rows=1000 loops=1) Hash Cond: ((t1.id_client = t2.id_client) AND (t1.fiscal_year = t2.fiscal_year) AND (t1.numero_compte = t2.numero_compte)) -> Subquery Scan on t1 (cost=2640.43..4121.08 rows=3290 width=434) (actual time=809.599..1146.165 rows=1000 loops=1) Filter: (t1.row_number > 2000) Rows Removed by Filter: 2000 -> WindowAgg (cost=2640.43..3997.69 rows=9871 width=434) (actual time=765.978..1144.400 rows=3000 loops=1) Filter: ((row_number() OVER (?)) < 3001) Rows Removed by Filter: 15188 -> WindowAgg (cost=2640.43..3405.43 rows=9871 width=198) (actual time=209.964..649.234 rows=18188 loops=1) -> WindowAgg (cost=2640.43..3133.98 rows=9871 width=134) (actual time=209.920..491.704 rows=18188 loops=1) Run Condition: (row_number() OVER (?) < 3001) -> WindowAgg (cost=2640.43..2936.56 rows=9871 width=126) (actual time=209.879..405.444 rows=18188 loops=1) -> Sort (cost=2640.43..2665.10 rows=9871 width=94) (actual time=209.829..220.354 rows=18188 loops=1) Sort Key: tbljournal.numero_compte, tbljournal.date_ecriture, tbljournal.id_line Sort Method: quicksort Memory: 3299kB -> Bitmap Heap Scan on tbljournal (cost=137.47..1985.54 rows=9871 width=94) (actual time=6.990..43.471 rows=18188 loops=1) Recheck Cond: ((id_client = 2739) AND (fiscal_year = 2024)) Heap Blocks: exact=857 -> Bitmap Index Scan on tbljournal_client_year_libelle_journal_idx (cost=0.00..135.00 rows=9871 width=0) (actual time=6.212..6.212 rows=18188 loops=1) Index Cond: ((id_client = 2739) AND (fiscal_year = 2024)) -> Hash (cost=187.55..187.55 rows=9955 width=36) (actual time=50.708..50.710 rows=9955 loops=1) Buckets: 16384 Batches: 1 Memory Usage: 813kB -> Seq Scan on tblcompte t2 (cost=0.00..187.55 rows=9955 width=36) (actual time=0.059..18.644 rows=9955 loops=1) Planning Time: 8.203 ms Execution Time: 1241.020 ms (28 rows) ################################# cat /proc/cpuinfo on i5-5300U ################################# processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 61 model name : Intel(R) Core(TM) i5-5300U CPU @ 2.30GHz stepping : 4 microcode : 0x2f cpu MHz : 2294.544 cache size : 3072 KB physical id : 0 siblings : 4 core id : 0 cpu cores : 2 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 20 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 cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm rdseed adx smap intel_pt xsaveopt dtherm ida arat pln pts md_clear flush_l1d ibpb_exit_to_user bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit srbds mmio_unknown vmscape bogomips : 4589.05 clflush size : 64 cache_alignment : 64 address sizes : 39 bits physical, 48 bits virtual power management: processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 61 model name : Intel(R) Core(TM) i5-5300U CPU @ 2.30GHz stepping : 4 microcode : 0x2f cpu MHz : 2294.489 cache size : 3072 KB physical id : 0 siblings : 4 core id : 0 cpu cores : 2 apicid : 1 initial apicid : 1 fpu : yes fpu_exception : yes cpuid level : 20 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 cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm rdseed adx smap intel_pt xsaveopt dtherm ida arat pln pts md_clear flush_l1d ibpb_exit_to_user bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit srbds mmio_unknown vmscape bogomips : 4589.05 clflush size : 64 cache_alignment : 64 address sizes : 39 bits physical, 48 bits virtual power management: processor : 2 vendor_id : GenuineIntel cpu family : 6 model : 61 model name : Intel(R) Core(TM) i5-5300U CPU @ 2.30GHz stepping : 4 microcode : 0x2f cpu MHz : 2294.371 cache size : 3072 KB physical id : 0 siblings : 4 core id : 1 cpu cores : 2 apicid : 2 initial apicid : 2 fpu : yes fpu_exception : yes cpuid level : 20 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 cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm rdseed adx smap intel_pt xsaveopt dtherm ida arat pln pts md_clear flush_l1d ibpb_exit_to_user bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit srbds mmio_unknown vmscape bogomips : 4589.05 clflush size : 64 cache_alignment : 64 address sizes : 39 bits physical, 48 bits virtual power management: processor : 3 vendor_id : GenuineIntel cpu family : 6 model : 61 model name : Intel(R) Core(TM) i5-5300U CPU @ 2.30GHz stepping : 4 microcode : 0x2f cpu MHz : 2294.392 cache size : 3072 KB physical id : 0 siblings : 4 core id : 1 cpu cores : 2 apicid : 3 initial apicid : 3 fpu : yes fpu_exception : yes cpuid level : 20 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 cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm rdseed adx smap intel_pt xsaveopt dtherm ida arat pln pts md_clear flush_l1d ibpb_exit_to_user bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit srbds mmio_unknown vmscape bogomips : 4589.05 clflush size : 64 cache_alignment : 64 address sizes : 39 bits physical, 48 bits virtual power management: -- vv.lists <[email protected]>
