LKML Archive on
help / color / mirror / Atom feed
Subject: [RFC PATCH 0/4] [RESEND] Change default MSGMNI tunable to scale with lowmem
Date: Mon, 14 Jan 2008 16:54:02 +0100	[thread overview]
Message-ID: <> (raw)

Resending the set of patches after Andrew's remark about the fact that we
should take the lowmem into account, rather than the total ram.

Also, these patches have been enhanced with memory hotplug management.

Note: they now have to applied to 2.6.24-rc7.


On large systems we'd like to allow a larger number of message queues.
In some cases up to 32K. However simply setting MSGMNI to a larger value may
cause problems for smaller systems.

The first patch of this series introduces a default maximum number of message
queue ids that scales with the amount of lowmem.

Since msgmni is per namespace and there is no amount of memory dedicated to
each namespace so far, the second patch of this series scales msgmni to
the number of ipc namespaces.

In the last patch, a notifier block is added to the ipc namespace structure to
manage memory hotplug. The callback routine is activated upon memory
add/remove and it recomputes msgmni. One callback routine is added to the
memory notifier chain each time an ipc namespace is allocated. It is removed
when the coresponding ipc namespace is freed.

I still have 1 issue that I'll try to solve next:
  . use the notification mechanism to recompute all the msg_ctlmni each time
    an ipc namespace is created / removed.

These patches should be applied to 2.6.24-rc7, in the following order:

[PATCH 1/4]: ipc_scale_msgmni_with_lowmem.patch
[PATCH 2/4]: ipc_scale_msgmni_with_namespaces.patch
[PATCH 3/4]: ipc_slab_memory_callback_prio_to_const.patch
[PATCH 4/4]: ipc_recompute_msgmni_on_memory_hotplug.patch



             reply	other threads:[~2008-01-14 15:57 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-01-14 15:54 Nadia.Derbey [this message]
2008-01-14 15:54 ` [RFC PATCH 1/4] [RESEND] Scaling msgmni to the amount of lowmem Nadia.Derbey
2008-01-14 15:54 ` [RFC PATCH 2/4] [RESEND] Scaling msgmni to the number of ipc namespaces Nadia.Derbey
2008-01-14 15:54 ` [RFC PATCH 3/4] [RESEND] Defining the slab_memory_callback priority as a constant Nadia.Derbey
2008-01-14 15:54 ` [RFC PATCH 4/4] [RESEND] Recomputing msgmni on memory add / remove Nadia.Derbey
2008-01-15  8:07   ` Yasunori Goto
2008-01-15  9:03     ` Nadia Derbey
2008-01-15  9:40       ` Yasunori Goto
2008-01-15 10:16         ` Nadia Derbey
2008-01-15  9:06 ` [RFC PATCH 0/4] [RESEND] Change default MSGMNI tunable to scale with lowmem Nadia Derbey
2008-01-15  9:21   ` Matt Helsley
2008-01-15 15:17 Nadia Derbey
2008-01-15 15:30 ` Nadia Derbey

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \
    --subject='Re: [RFC PATCH 0/4] [RESEND] Change default MSGMNI tunable to scale with lowmem' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).