Hi Robert,
We are trying to understand why pgbench on AIX is slower compared to Linux/Power on the same HW/Disks. So, we have yet no idea about what may be the root cause and what should be changed. So, changing: dynamic_shared_memory_type = sysv seems to help. And maybe changing the main shared memory segment could also improve the performance. However, how one can change this? Cordialement, Tony Reix tony.r...@atos.net ATOS / Bull SAS ATOS Expert IBM Coop Architect & Technical Leader Office : +33 (0) 4 76 29 72 67 1 rue de Provence - 38432 Échirolles - France www.atos.net<https://mail.ad.bull.net/owa/redir.aspx?C=PvphmPvCZkGrAgHVnWGsdMcDKgzl_dEIsM6rX0g4u4v8V81YffzBGkWrtQeAXNovd3ttkJL8JIc.&URL=http%3a%2f%2fwww.atos.net%2f> ________________________________ De : Robert Haas <robertmh...@gmail.com> Envoyé : mardi 20 novembre 2018 13:53:53 À : REIX, Tony Cc : pgsql-hack...@postgresql.org; EMPEREUR-MOT, SYLVIE Objet : Re: Shared Memory: How to use SYSV rather than MMAP ? On Tue, Nov 20, 2018 at 5:11 AM REIX, Tony <tony.r...@atos.net> wrote: > On AIX, since with MMAP we have only 4K pages though we can have 64K pages > with SYSV, we'd like to experiment with SYSV rather than MMAP and measure the > impact to the performance. Are you trying to move the main shared memory segment or the dynamic shared memory segments? -- Robert Haas EnterpriseDB: https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.enterprisedb.com&data=01%7C01%7Ctony.reix%40atos.net%7C09c690fe81b9489e135d08d64ee74b7f%7C33440fc6b7c7412cbb730e70b0198d5a%7C0&sdata=oj%2Fd7djWk16Bb8%2F2I9eiqlWnRBfcFNjYtZCj%2FHd3Qp0%3D&reserved=0 The Enterprise PostgreSQL Company
