Re: [PERFORM] Stalls on PGSemaphoreLock

2014-04-22 Thread Matheus de Oliveira
On Tue, Apr 22, 2014 at 12:12 PM, Matthew Spilich wrote: > Hi all - I am a little delayed in reporting back on this issue, but it > was indeed the hugepage defrag setting that was the cause of my issue. > The transparent huge pages features seems so bogus for database workloads, that it is one o

Re: [PERFORM] Stalls on PGSemaphoreLock

2014-04-22 Thread Matthew Spilich
rt de Matthew Spilich Envoyé : mardi 25 mars 2014 19:38 À : pgsql-performance@postgresql.org Objet : Re: [PERFORM] Stalls on PGSemaphoreLock Thanks all: Ray: Thanks, we started to look at the hardware/firmware, but didn't get to the the level of detail or running sar. I will probably collect m

Re: [PERFORM] Stalls on PGSemaphoreLock

2014-03-27 Thread Gudmundsson Martin (mg)
formance-ow...@postgresql.org [mailto:pgsql-performance- > ow...@postgresql.org] On Behalf Of Pavy Philippe > Sent: den 25 mars 2014 9:10 > To: Matthew Spilich; pgsql-performance@postgresql.org > Subject: Re: [PERFORM] Stalls on PGSemaphoreLock > > Here, we were the transparent hugepage always act

Re: [PERFORM] Stalls on PGSemaphoreLock

2014-03-26 Thread Pavy Philippe
nvoyé : mardi 25 mars 2014 19:38 À : pgsql-performance@postgresql.org Objet : Re: [PERFORM] Stalls on PGSemaphoreLock Thanks all: Ray: Thanks, we started to look at the hardware/firmware, but didn't get to the the level of detail or running sar. I will probably collect more detail in this

RE : [PERFORM] Stalls on PGSemaphoreLock

2014-03-26 Thread Pavy Philippe
pgsql-performance@postgresql.org Objet : Re: [PERFORM] Stalls on PGSemaphoreLock On Mar 25, 2014, at 8:46 AM, Matthew Spilich wrote: The symptom: The database machine (running postgres 9.1.9 on CentOS 6.4) is running a low utilization most of the time, but once every day or two, it will appear to

Re: [PERFORM] Stalls on PGSemaphoreLock

2014-03-25 Thread Takashi Horikawa
On Mar 25, 2014, at 8:46 AM, Matthew Spilich wrote: > Has any on the forum seen something similar? I think I reported similar phenomenon in my SIGMOD 2013 paper (Latch-free data structures for DBMS: design, implementation, and evaluation, ). > - 4

Re: [PERFORM] Stalls on PGSemaphoreLock

2014-03-25 Thread Emre Hasegeli
2014-03-25, Matthew Spilich : > Has any on the forum seen something similar? Any suggestions on what > to look at next?If it is helpful to describe the server hardware, it's > got 2 E5-2670 cpu and 256 GB of ram, and the database is hosted on 1.6TB raid > 10 local storage (15K 300 GB drives

Re: [PERFORM] Stalls on PGSemaphoreLock

2014-03-25 Thread Matthew Spilich
...@worldline.com] Sent: Tuesday, March 25, 2014 1:45 PM To: Ray Stell; Matthew Spilich Cc: pgsql-performance@postgresql.org Subject: RE : [PERFORM] Stalls on PGSemaphoreLock Hello Recently I have a similar problem. The first symptom was a freeze of the connection and 100% of CPU SYS dur

Re: [PERFORM] Stalls on PGSemaphoreLock

2014-03-25 Thread Ray Stell
On Mar 25, 2014, at 8:46 AM, Matthew Spilich wrote: > The symptom: The database machine (running postgres 9.1.9 on CentOS 6.4) is > running a low utilization most of the time, but once every day or two, it > will appear to slow down to the point where queries back up and clients are > unable