Re: Supporting huge pages on Windows - Mailing list pgsql-hackers

From Tsunakawa, Takayuki
Subject Re: Supporting huge pages on Windows
Date
Msg-id 0A3221C70F24FB45833433255569204D1F5F2D89@G01JPEXMBYT05
Whole thread Raw
In response to Re: Supporting huge pages on Windows  (Thomas Munro <thomas.munro@enterprisedb.com>)
Responses Re: Supporting huge pages on Windows  (Thomas Munro <thomas.munro@enterprisedb.com>)
List pgsql-hackers
From: Thomas Munro [mailto:thomas.munro@enterprisedb.com]
> >  huge_pages=off: 70412 tps
> >  huge_pages=on : 72100 tps
> 
> Hmm.  I guess it could be noise or random code rearrangement effects.

I'm not the difference was a random noise, because running multiple set of three runs of pgbench (huge_pages = on, off,
on,off, on...) produced similar results.  But I expected a bit greater improvement, say, +10%.  There may be better
benchmarkmodel where the large page stands out, but I think pgbench is not so bad because its random data access would
causeTLB cache misses.
 



> I saw your recent post[2] proposing to remove the sentence about the 512MB
> effective limit and I wondered why you didn't go to larger sizes with a
> larger database and more run time.  But I will let others with more
> benchmarking experience comment on the best approach to investigate Windows
> shared_buffers performance.

Yes, I could have gone to 8GB of shared_buffers because my PC has 16GB of RAM, but I felt the number of variations was
sufficient. Anyway, positive comments on benchmarking would be appreciated.
 

Regards
Takayuki Tsunakawa



pgsql-hackers by date:

Previous
From: Ashutosh Bapat
Date:
Subject: Re: Transactions involving multiple postgres foreign servers
Next
From: Piotr Stefaniak
Date:
Subject: Re: LLVM Address Sanitizer (ASAN) and valgrind support