Hi All,

Pls help me with the below queries :

1) Why 64KB pages are not supported on my system where as these should
have been enabled by default? - The pagesize -af command only displays
4K and 16M supported pages.

2) I have not set the 16MB pages as shown in the vmo -L output but the
pagesize command still shows it.

# vmo -L | grep lgpg_size
lgpg_size

NAME CUR DEF BOOT MIN MAX UNIT
lgpg_size 0 0 0 0 16M
bytes

TIA
Regrads,
Ashok Sangra

what system do you have ? what oslevel and microcode level ?

Ref: http://www-03.ibm.com/servers/aix/wh...tiple_page.pdf

Introduction / Overview

The POWER5+â„¢ processor and AIX 5Lâ„¢ Version 5.3 with the 5300-04
Recommended
Maintenance Package introduce support for two new virtual memory page
sizes – 64KB
and 16GB. Using larger virtual memory page sizes for an application’s
memory can
significantly improve an application's performance and throughput due
to hardware
efficiencies associated with larger page sizes. While 16GB pages are
intended to only be
used in very high-performance environments, 64KB pages are general-
purpose, and most
workloads will likely see a benefit by using 64KB pages rather than
4KB pages. This
document gives an overview of the new multiple page size support of
AIX 5L and how a
user can use these new page sizes for an application’s memory to
potentially improve
performance.

Software Requirements

AIX 5L Version 5.3 with the 5300-04 Recommended Maintenance Package is
required
for 64KB and 16GB page size support.
The minimum IBM System p5â„¢ microcode level required for 64KB and 16GB
page size
support is p5 System Release 240, Service Level 202.
In order to allocate 16GB huge pages on a system, Version 5 Release 2
of the Hardware
Management Console (HMC) machine code is required.
Supported page sizes

AIX 5L Version 5.3 with the 5300-04 Recommended Maintenance Package
supports up
to four different page sizes, but the actual page sizes supported by a
particular system will
vary based on processor type. The following table lists the page sizes
supported by
AIX 5L Version 5.3 with the 5300-04 Recommended Maintenance Package
and required

System pâ„¢ hardware:

Page Size Required Hardware Requires UserConfiguration Restricted
Kernel
4KB ALL No No 64 & 32
64KB IBM POWER5+â„¢ or later No No 64 only
16MB POWER4â„¢ or later Yes Yes 64 & 32
16GB POWER5+ or later Yes Yes 64 only
As with all previous versions of AIX® and AIX 5L, 4KB is the default
page size for
AIX 5L Version 5.3 with the 5300-04 Recommended Maintenance Package. A
process
will continue to use 4KB pages unless a user specifically requests
another page size be
used.

64KB Page Size Support

On POWER5+ systems, AIX 5L Version 5.3 with the 5300-04 Recommended
Maintenance Package supports a new 64KB page size when running the 64-
bit kernel.
AIX 5L has rich support around 64KB pages, and 64KB pages are intended
to be generalpurpose.
64KB pages are very easy to use, and it is expected that many
applications will
see performance benefits when using 64KB pages rather than 4KB pages.
No system configuration changes are necessary to enable a system to
use 64KB
pages. On systems that support 64KB pages, the AIX 5L kernel will
automatically
configure 64KB pages for the system. 64KB pages are fully pageable,
and the size of the
pool of 64KB page frames on a system is dynamic and fully managed by
AIX 5L.
AIX 5L will vary the number of 4KB and 64KB page frames on a system to
meet
demand on the different page sizes. Both the svmon and vmstat commands
can be used
to monitor the number of 4KB and 64KB page frames on a system.

Rgds
Mark Taylor

On Mar 30, 4:07Â*am, "Mark Taylor" <m...@talk21.com> wrote:
> what system do you have ? what oslevel and microcode level ?
>
> Ref:http://www-03.ibm.com/servers/aix/wh...tiple_page.pdf
>
> Introduction / Overview
>
> The POWER5+â„¢ processor and AIX 5Lâ„¢ Version 5.3 with the 5300-04
> Recommended
> Maintenance Package introduce support for two new virtual memory page
> sizes – 64KB
> and 16GB. Using larger virtual memory page sizes for an application’s
> memory can
> significantly improve an application's performance and throughput due
> to hardware
> efficiencies associated with larger page sizes. While 16GB pages are
> intended to only be
> used in very high-performance environments, 64KB pages are general-
> purpose, and most
> workloads will likely see a benefit by using 64KB pages rather than
> 4KB pages. This
> document gives an overview of the new multiple page size support of
> AIX 5L and how a
> user can use these new page sizes for an application’s memory to
> potentially improve
> performance.
>
> Software Requirements
>
> AIX 5L Version 5.3 with the 5300-04 Recommended Maintenance Package is
> required
> for 64KB and 16GB page size support.
> The minimum IBM System p5â„¢ microcode level required for 64KB and 16GB
> page size
> support is p5 System Release 240, Service Level 202.
> In order to allocate 16GB huge pages on a system, Version 5 Release 2
> of the Hardware
> Management Console (HMC) machine code is required.
> Supported page sizes
>
> AIX 5L Version 5.3 with the 5300-04 Recommended Maintenance Package
> supports up
> to four different page sizes, but the actual page sizes supported by a
> particular system will
> vary based on processor type. The following table lists the page sizes
> supported by
> AIX 5L Version 5.3 with the 5300-04 Recommended Maintenance Package
> and required
>
> System pâ„¢ hardware:
>
> Page Size Required Hardware Requires UserConfiguration Restricted
> Kernel
> 4KB ALL No No 64 & 32
> 64KB IBM POWER5+â„¢ or later No No 64 only
> 16MB POWER4â„¢ or later Yes Yes 64 & 32
> 16GB POWER5+ or later Yes Yes 64 only
> As with all previous versions of AIX® and AIX 5L, 4KB is the default
> page size for
> AIX 5L Version 5.3 with the 5300-04 Recommended Maintenance Package. A
> process
> will continue to use 4KB pages unless a user specifically requests
> another page size be
> used.
>
> 64KB Page Size Support
>
> On POWER5+ systems, AIX 5L Version 5.3 with the 5300-04 Recommended
> Maintenance Package supports a new 64KB page size when running the 64-
> bit kernel.
> AIX 5L has rich support around 64KB pages, and 64KB pages are intended
> to be generalpurpose.
> 64KB pages are very easy to use, and it is expected that many
> applications will
> see performance benefits when using 64KB pages rather than 4KB pages.
> No system configuration changes are necessary to enable a system to
> use 64KB
> pages. On systems that support 64KB pages, the AIX 5L kernel will
> automatically
> configure 64KB pages for the system. 64KB pages are fully pageable,
> and the size of the
> pool of 64KB page frames on a system is dynamic and fully managed by
> AIX 5L.
> AIX 5L will vary the number of 4KB and 64KB page frames on a system to
> meet
> demand on the different page sizes. Both the svmon and vmstat commands
> can be used
> to monitor the number of 4KB and 64KB page frames on a system.
>
> Rgds
> Mark Taylor

Hi Mark

The CPU is PowerPC_POWER5
OS level is 5300-04
Microcode level is SF240_219
pagesize -af shows 4K and 16M

-Ashok

> The CPU is PowerPC_POWER5
> OS level is 5300-04
> Microcode level is SF240_219
> pagesize -af shows 4K and 16M
>
> -Ashok

"On POWER5+ systems, AIX 5L Version 5.3 with the 5300-04 Recommended
Maintenance Package supports a new 64KB page size when running the 64-
bit kernel"

So, Do you have p5+ and 64bit kernel ?

On Mar 30, 9:14 am, "Mark Taylor" <m...@talk21.com> wrote:
> > The CPU is PowerPC_POWER5
> > OS level is 5300-04
> > Microcode level is SF240_219
> > pagesize -af shows 4K and 16M
>
> > -Ashok
>
> "On POWER5+ systems, AIX 5L Version 5.3 with the 5300-04 Recommended
> Maintenance Package supports a new 64KB page size when running the 64-
> bit kernel"
>
> So, Do you have p5+ and 64bit kernel ?

Kernal : 64 Bit
CPU : 64 Bit
OSlevel : 5300-04
Processor : PowerPC_POWER5 (not sure if this is POWER5+)