From: Paul Moore <paul@paul-moore.com>
To: Max Englander <max.englander@gmail.com>, sgrubb@redhat.com
Cc: linux-audit@redhat.com
Subject: Re: [PATCH v3] audit: report audit wait metric in audit status reply
Date: Tue, 21 Jul 2020 11:26:53 -0400 [thread overview]
Message-ID: <CAHC9VhQ_JjYJxP6t74bbeBvf5g0TGJZMfLtq0y0aia8y+Dm4fQ@mail.gmail.com> (raw)
In-Reply-To: <CAHC9VhQNpAeUKtDZJ7+Unq=NeHNc4Wjxo9E1d4m8P6STm+5+3w@mail.gmail.com>
On Wed, Jul 15, 2020 at 9:30 PM Paul Moore <paul@paul-moore.com> wrote:
> On Wed, Jul 8, 2020 at 7:13 PM Paul Moore <paul@paul-moore.com> wrote:
> > On Sat, Jul 4, 2020 at 11:15 AM Max Englander <max.englander@gmail.com> wrote:
> > >
> > > In environments where the preservation of audit events and predictable
> > > usage of system memory are prioritized, admins may use a combination of
> > > --backlog_wait_time and -b options at the risk of degraded performance
> > > resulting from backlog waiting. In some cases, this risk may be
> > > preferred to lost events or unbounded memory usage. Ideally, this risk
> > > can be mitigated by making adjustments when backlog waiting is detected.
> > >
> > > However, detection can be difficult using the currently available
> > > metrics. For example, an admin attempting to debug degraded performance
> > > may falsely believe a full backlog indicates backlog waiting. It may
> > > turn out the backlog frequently fills up but drains quickly.
> > >
> > > To make it easier to reliably track degraded performance to backlog
> > > waiting, this patch makes the following changes:
> > >
> > > Add a new field backlog_wait_time_total to the audit status reply.
> > > Initialize this field to zero. Add to this field the total time spent
> > > by the current task on scheduled timeouts while the backlog limit is
> > > exceeded. Reset field to zero upon request via AUDIT_SET.
> > >
> > > Tested on Ubuntu 18.04 using complementary changes to the
> > > audit-userspace and audit-testsuite:
> > > - https://github.com/linux-audit/audit-userspace/pull/134
> > > - https://github.com/linux-audit/audit-testsuite/pull/97
> > >
> > > Signed-off-by: Max Englander <max.englander@gmail.com>
> > > ---
> > > Patch changelogs between v1 and v2:
> > > - Instead of printing a warning when backlog waiting occurs, add
> > > duration of backlog waiting to cumulative sum, and report this
> > > sum in audit status reply.
> > >
> > > Patch changelogs between v2 and v3:
> > > - Rename backlog_wait_sum to backlog_wait_time_actual.
> > > - Drop unneeded and unwanted header flags
> > > AUDIT_FEATURE_BITMAP_BACKLOG_WAIT_SUM and
> > > AUDIT_VERSION_BACKLOG_WAIT_SUM.
> > > - Increment backlog_wait_time_actual counter after every call to
> > > schedule_timeout rather than once after enqueuing (or losing) an
> > > audit record.
> > > - Add support for resetting backlog_wait_time_actual counter to zero
> > > upon request via AUDIT_SET.
> > >
> > > include/uapi/linux/audit.h | 18 +++++++++++-------
> > > kernel/audit.c | 35 +++++++++++++++++++++++++----------
> > > 2 files changed, 36 insertions(+), 17 deletions(-)
> >
> > This looks okay to me, thanks for the fixes Max.
> >
> > Steve, does the associated userspace patch look okay to you?
>
> Steve, any comments on the userspace patch? Did I miss a reply in my
> inbox perhaps?
>
> If I don't see any feedback by the end of the week I'll plan on
> merging this into audit/next.
It's been over two weeks with no comment, so I went ahead and merged
this into audit/next. Thanks for your patience Max!
--
paul moore
www.paul-moore.com
--
Linux-audit mailing list
Linux-audit@redhat.com
https://www.redhat.com/mailman/listinfo/linux-audit
next prev parent reply other threads:[~2020-07-21 15:27 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-04 15:15 [PATCH v3] audit: report audit wait metric in audit status reply Max Englander
2020-07-08 23:13 ` Paul Moore
2020-07-16 1:30 ` Paul Moore
2020-07-21 15:26 ` Paul Moore [this message]
2020-07-21 22:59 ` Max Englander
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:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAHC9VhQ_JjYJxP6t74bbeBvf5g0TGJZMfLtq0y0aia8y+Dm4fQ@mail.gmail.com \
--to=paul@paul-moore.com \
--cc=linux-audit@redhat.com \
--cc=max.englander@gmail.com \
--cc=sgrubb@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).