IDS Forum

Re: Large Pages on AIX

Posted By: Art Kagel
Date: Thursday, 5 April 2012, at 12:54 p.m.

In Response To: Re: Large Pages on AIX (Peter_Logan@spartanstores.com)

The seen to improve memory access times noticably on every system that
supports them (AIX, Solaris, & Linux IB).

Art

Art S. Kagel
Advanced DataTools (www.advancedatatools.com)
Blog: http://informix-myview.blogspot.com/

Disclaimer: Please keep in mind that my own opinions are my own opinions
and do not reflect on my employer, Advanced DataTools, the IIUG, nor any
other organization with which I am associated either explicitly,
implicitly, or by inference. Neither do those opinions reflect those of
other individuals affiliated with any entity with which I am affiliated nor
those of the entities themselves.

On Thu, Apr 5, 2012 at 10:49 AM, Peter_Logan@spartanstores.com <
Peter_Logan@spartanstores.com> wrote:

> Are there any general guidelines that exist on when you should use large=20
> pages?
>
> Peter Logan
> Senior Database Administrator
> Phone: 616/878-8309
>
> From: "NEIL TRUBY" <neil.truby@ardenta.com>
> To: ids@iiug.org
> Date: 04/05/2012 09:33 AM
> Subject: Large Pages on AIX [26661]
> Sent by: ids-bounces@iiug.org
>
> 11.70FC4 on AIX 6.1=20
>
> We?re being told that we should enable LARGEPAGES for fast
> initialisation=20
> and=20
> performance.=20
>
> But, it?s not working for some reason:=20
>
> The relevant variables are set ?.=20
> $ onstat -c | grep RESIDE=20
> # RESIDENT - Controls whether shared memory is resident.=20
> RESIDENT 1=20
> $ env | grep IFX=20
> IFX=5FLARGE=5FPAGES=3D1=20
>
> $ onmode -ky ; oninit -v=20
>
> And we get the ?will try to use large pages message?:=20
>
> 20:07:06 IBM Informix Dynamic Server Started.=20
> 20:07:06 Requested shared memory segment size rounded from 133984KB to=20
> 262144KB=20
> 20:07:06 Shared memory segment will use large pages if available.=20
> 20:07:07 Segment locked: addr=3D700000010000000, size=3D268435456=20
> 20:07:08 VP pid=3D2032150 priority fixed at 60=20
>
> Thu Apr 5 20:07:08 2012=20
>
> 20:07:08 Event alarms enabled. ALARMPROG =3D=20
> '/opt/informix/INST1/scripts/alarmprogram.sh'=20
> 20:07:08 Dynamically allocated new virtual shared memory segment (size=20
> 1048576KB)=20
> 20:07:08 Memory sizes:resident:262144 KB, virtual:1058816 KB, no
> SHMTOTAL=20
> limit=20
> 20:07:08 Booting Language <c> from module <>=20
> 20:07:08 Loading Module <CNULL>=20
> 20:07:08 Booting Language <builtin> from module <>=20
> 20:07:08 Loading Module <BUILTINNULL>=20
> 20:07:14 DR: DRAUTO is 0 (Off)=20
> 20:07:14 DR: ENCRYPT=5FHDR is 0 (HDR encryption Disabled)=20
> 20:07:14 AIX MP latch code enabled=20
> 20:07:14 Requested shared memory segment size rounded from 548KB to
> 560KB=20
> 20:07:14 Dynamically allocated new message shared memory segment (size=20
> 560KB)=20
> 20:07:14 Memory sizes:resident:262144 KB, virtual:1059376 KB, no
> SHMTOTAL=20
> limit=20
> 20:07:14 Requested shared memory segment size rounded from 548KB to
> 560KB=20
> 20:07:14 Dynamically allocated new message shared memory segment (size=20
> 560KB)=20
> 20:07:14 Memory sizes:resident:262144 KB, virtual:1059936 KB, no
> SHMTOTAL=20
> limit=20
> 20:07:14 Fast poll pollset enabled.=20
> 20:07:14 IBM Informix Dynamic Server Version 11.70.FC4 Software Serial=20
> Number=20
> AAA#B000000=20
> 20:07:15 IBM Informix Dynamic Server Initialized -- Shared Memory=20
> Initialized.=20
>
> ? but it doesn?t &#61516;:=20
>
> svmon -G=20
>
> size inuse free pin virtual mmode=20
> memory 31522816 22513142 9009674 22097181 2011105 Ded=20
> pg space 131072 4806=20
>
> work pers clnt other=20
> pin 699341 0 0 934224=20
> in use 2011105 0 38421=20
>
> PageSize PoolSize inuse pgsp pin virtual=20
> s 4 KB - 1367030 4806 1260061 1328609=20
> m 64 KB - 42656 0 23344 42656=20
> L 16 MB 4996 0 0 4996 0=20
>
> Any ideas please? probably something really stupid and obvious.=20
>
> Thanks=20
> Neil=20
>
>
> ***************************************************************************=
> ****=20
>
> Forum Note: Use "Reply" to post a response in the discussion forum.=20
>
>
>
> *******************************************************************************
> Forum Note: Use "Reply" to post a response in the discussion forum.
>
>

--e89a8f3ba959914aa604bcf1642c

Messages In This Thread

• Large Pages on AIX
  NEIL TRUBY -- Thursday, 5 April 2012, at 9:33 a.m.
  • Re: Large Pages on AIX
    Peter_Logan@spartanstores.com -- Thursday, 5 April 2012, at 10:49 a.m.
    • Re: Large Pages on AIX
      NEIL TRUBY -- Thursday, 5 April 2012, at 10:53 a.m.
    • Re: Large Pages on AIX
      Art Kagel -- Thursday, 5 April 2012, at 12:54 p.m.
  • Re: Large Pages on AIX
    Cesar Inacio Martins -- Thursday, 5 April 2012, at 4:30 p.m.
    • Re: Large Pages on AIX
      Eric Rowell -- Thursday, 5 April 2012, at 6:27 p.m.

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