mbuma is an Mbuf & Cluster allocator built on top of a number of
extensions to the UMA framework, all included herein.
Extensions to UMA worth noting:
- Better layering between slab <-> zone caches; introduce
Keg structure which splits off slab cache away from the
zone structure and allows multiple zones to be stacked
on top of a single Keg (single type of slab cache);
perhaps we should look into defining a subset API on
top of the Keg for special use by malloc(9),
for example.
- UMA_ZONE_REFCNT zones can now be added, and reference
counters automagically allocated for them within the end
of the associated slab structures. uma_find_refcnt()
does a kextract to fetch the slab struct reference from
the underlying page, and lookup the corresponding refcnt.
mbuma things worth noting:
- integrates mbuf & cluster allocations with extended UMA
and provides caches for commonly-allocated items; defines
several zones (two primary, one secondary) and two kegs.
- change up certain code paths that always used to do:
m_get() + m_clget() to instead just use m_getcl() and
try to take advantage of the newly defined secondary
Packet zone.
- netstat(1) and systat(1) quickly hacked up to do basic
stat reporting but additional stats work needs to be
done once some other details within UMA have been taken
care of and it becomes clearer to how stats will work
within the modified framework.
From the user perspective, one implication is that the
NMBCLUSTERS compile-time option is no longer used. The
maximum number of clusters is still capped off according
to maxusers, but it can be made unlimited by setting
the kern.ipc.nmbclusters boot-time tunable to zero.
Work should be done to write an appropriate sysctl
handler allowing dynamic tuning of kern.ipc.nmbclusters
at runtime.
Additional things worth noting/known issues (READ):
- One report of 'ips' (ServeRAID) driver acting really
slow in conjunction with mbuma. Need more data.
Latest report is that ips is equally sucking with
and without mbuma.
- Giant leak in NFS code sometimes occurs, can't
reproduce but currently analyzing; brueffer is
able to reproduce but THIS IS NOT an mbuma-specific
problem and currently occurs even WITHOUT mbuma.
- Issues in network locking: there is at least one
code path in the rip code where one or more locks
are acquired and we end up in m_prepend() with
M_WAITOK, which causes WITNESS to whine from within
UMA. Current temporary solution: force all UMA
allocations to be M_NOWAIT from within UMA for now
to avoid deadlocks unless WITNESS is defined and we
can determine with certainty that we're not holding
any locks when we're M_WAITOK.
- I've seen at least one weird socketbuffer empty-but-
mbuf-still-attached panic. I don't believe this
to be related to mbuma but please keep your eyes
open, turn on debugging, and capture crash dumps.
This change removes more code than it adds.
A paper is available detailing the change and considering
various performance issues, it was presented at BSDCan2004:
http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf
Please read the paper for Future Work and implementation
details, as well as credits.
Testing and Debugging:
rwatson,
brueffer,
Ketrien I. Saihr-Kesenchedra,
...
Reviewed by: Lots of people (for different parts)
the depth of the current file relative to the starting
point of the traversal is n. The usual +/- modifiers
to the argument apply.
- while I'm here, fix -maxdepth in the case of a depth-first
traversal
Print the top ten maintainers of python module ports
(works with p5-* too):
find /usr/ports -depth 2 \! -name 'py-*' -prune -o \
-depth 3 -name Makefile -execdir make -VMAINTAINER \; \
| sort | uniq -c | sort -nr | head
PR: 66667
Reviewed by: ru, joerg
Approved by: joerg
MFC after: 2 weeks
* Move format/compression reporting to end of output, since
we don't always know the input format until then.
* Set bsdtar exit value to 1 if any file could not be restored.
* Generate gtar-style warning when stripping leading '/' characters.
* Warn when removing symlinks.
Note that bsdtar's -o (which follows SUSv2) is not the same as GNU tar's -o.
In GNU tar, -o and --no-same-owner are not synonyms.
Pointed out by: Kris Kennaway (required by xpenguins port)
with "-t" rather than absolute timestamps. This allows the reader
to get a better sense of latency between events, such as time to
schedule an interrupt thread from time the interrupt occurred. Assert
a copyright on ktrdump.c since I seem to be modifying it more than I
thought.
"file and line" field consistently; previously, a 32-character field
length was used for the table header, which resulted in the header
not lining up with the table.
use fseeko(3) instead.
This commit fixes breakage when `lastcomm matchstring` is run.
PR: bin/66765, bin/64568
Submitted by: Dan Nelson <dnelson at allantgroup.com>
1) Missing include for declaration of time conversion functions.
2) Avoid a couple of alignment warnings on 64 bit arches by memcpying the
things pointed to by caddrs into variables of the right type.
Bump WARNS to 6 while I'm here.
