based by vmalloc()'ed memory. I now alloc a slab which is
roughly 32*spl_obj_size and in this block of memory I place
the slab descriptor, slab object descriptors, and objects
themselves. This greatly reduces vmalloc lock contention.
Still some minor cleanup remains and fine tuning but
it's working pretty well.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@139 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
well for the expected workloads. Improvement in this commit include:
- Added DEBUG_KMEM_TRACKING #define which can optionally be set
when DEBUG_KMEM is defined to do per allocation tracking. This
allows us to get all the lightweight kmem debugging enabled by
default which is pretty light weight, and only when looking
for a memory leak we can briefly enable the per alloc tracking.
- Added set_normalized_timespec() in to SPL to simply using
the timespec() primatives from within a module.
- Added per-spinlock cycle counters to the slab in an attempt
to run down a lock contention issue. The contended lock
was in vmalloc() but I'm going to leave the cycle counters
in place for a little while until I'm convinced there arn't
other locking improvement possible in the slab.
- Added a proc interface to the slab to export per slab
cache statistics to /proc/spl/kmem/slab for analysis.
- Reworked spl_slab_alloc() function to allocate from kmem for
small allocation and vmem for large allocations. This improved
things considerably but futher work is needed.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@138 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
when repopulating it. Plus I fixed a few more suble races in
that part of the code which were catching me. Finally I fixed
a small race in kmem_test8.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@137 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
factor of 10x improvement on SMP system due to reduced lock contention.
This may put me in the ballpark of what is needed. We can still further
improve things on NUMA systems by creating an additional L3 cache per
memory node instead of the current global pool. With luck this won't
be needed. I should also take another look at the locking now that
everything is working. There's a good chance I can tighten it up a
little bit and improve things a little more.
kmem_lock: time (sec) slabs objs hash
kmem_lock: tot/max/calc tot/max/calc size/depth
kmem_lock: 0.000999926 6/6/1 192/192/32 32768/0
kmem_lock: 0.000999926 4/4/2 128/128/64 32768/0
kmem_lock: 0.000999926 4/4/4 128/128/128 32768/0
kmem_lock: 0.000999926 4/4/8 128/128/256 32768/0
kmem_lock: 0.000999926 4/4/16 128/128/512 32768/0
kmem_lock: 0.000999926 4/4/32 128/128/1024 32768/0
kmem_lock: 0.000999926 4/4/64 128/128/2048 32768/0
kmem_lock: 0.000999926 8/8/128 256/256/4096 32768/0
kmem_lock: 0.003999704 24/23/256 768/736/8192 32768/1
kmem_lock: 0.012999038 44/41/512 1408/1312/16384 32768/1
kmem_lock: 0.051996153 96/93/1024 3072/2976/32768 32768/2
kmem_lock: 0.181986536 187/184/2048 5984/5888/65536 32768/3
kmem_lock: 0.655951469 342/339/4096 10944/10848/131072 32768/4
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@136 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
to be overly clever and the context switch when the semaphore was busy
was destroying performance. Converting to a simple spin lock bough me
a factor of 50 or so. That said it's still not good enough. Tests
show bad performance and we are still CPU bound. The logical fix is
I need to implement per-cpu hot caches to minimize the SMP contention.
Linux and Solaris both have this, I was hoping to do without but it
looks like that's not to be.
kmem_lock: time (sec) slabs objs hash
kmem_lock: tot/max/calc tot/max/calc size/depth
kmem_lock: 0.022000000 7/6/64 224/177/2048 32768/1
kmem_lock: 0.039000000 13/13/128 416/404/4096 32768/1
kmem_lock: 0.079000000 23/21/256 736/672/8192 32768/1
kmem_lock: 0.158000000 48/47/512 1536/1504/16384 32768/1
kmem_lock: 0.345000000 105/105/1024 3360/3358/32768 32768/2
kmem_lock: 0.760000000 202/200/2048 6464/6400/65536 32768/3
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@135 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
allocator. I have serious contention issues here and I needed
a way to easily measure how much the following batch of changes
will improve things. Currently things are quite bad when the
allocator is highly contended, and interestingly it seems to
get worse in a non-linear fashion... I'm not sure why yet.
I'll figure it out tomorrow.
kmem:kmem_lock Pass
kmem_lock: time (sec) slabs objs
kmem_lock: tot/max/calc tot/max/calc
kmem_lock: 0.061000000 75/60/64 2400/1894/2048
kmem_lock: 0.157000000 134/125/128 4288/3974/4096
kmem_lock: 0.471000000 263/249/256 8416/7962/8192
kmem_lock: 2.526000000 518/499/512 16576/15957/16384
kmem_lock: 14.393000000 990/978/1024 31680/31270/32768
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@134 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
longer be based on the linux slab but to be its own complete
implementation. The new slab behaves much more like the
Solaris slab than the Linux slab.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@132 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
and a hang on subsequent sys_close. I'm not quite sure why the Fedora
kernel caught this bug the Chaos kernel did not, but I'm glad!
Convert remaining BUG_ON's to ASSERTs
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@122 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
working on this branch for the next few days I suggested you work
off of the 0.3.1 tag. The following changes are fairly extensive
and are designed to make the SPL compatible with all kernels in
the range of 2.6.18-2.6.25. There were 13 relevant API changes
between these releases and I have added the needed autoconf tests
to check for them. However, this has not all been tested extensively.
I'll sort of the breakage on Fedora Core 9 and RHEL5 this week.
SPL_AC_TYPE_UINTPTR_T
SPL_AC_TYPE_KMEM_CACHE_T
SPL_AC_KMEM_CACHE_DESTROY_INT
SPL_AC_ATOMIC_PANIC_NOTIFIER
SPL_AC_3ARGS_INIT_WORK
SPL_AC_2ARGS_REGISTER_SYSCTL
SPL_AC_KMEM_CACHE_T
SPL_AC_KMEM_CACHE_CREATE_DTOR
SPL_AC_3ARG_KMEM_CACHE_CREATE_CTOR
SPL_AC_SET_SHRINKER
SPL_AC_PATH_IN_NAMEIDATA
SPL_AC_TASK_CURR
SPL_AC_CTL_UNNUMBERED
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@119 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
- Detailed kmem memory allocation tracking. We can now get on
spl module unload a list of all memory allocations which were
not free'd and where the original alloc was. E.g.
SPL: 15554:632:(spl-kmem.c:442:kmem_fini()) kmem leaked 90/319332 bytes
SPL: 15554:648:(spl-kmem.c:451:kmem_fini()) address size data func:line
SPL: 15554:648:(spl-kmem.c:457:kmem_fini()) ffff8100734b68b8 32 0100000001005a5a __spl_mutex_init:70
SPL: 15554:648:(spl-kmem.c:457:kmem_fini()) ffff8100734b6148 13 &tl->tl_lock __spl_mutex_init:74
SPL: 15554:648:(spl-kmem.c:457:kmem_fini()) ffff81007ac43730 32 0100000001005a5a __spl_mutex_init:70
SPL: 15554:648:(spl-kmem.c:457:kmem_fini()) ffff81007ac437d8 13 &tl->tl_lock __spl_mutex_init:74
- Shift to using rwsems in kmem implmentation, to simply locking and
improve concurency.
- Shift to using rwsems in mutex implementation, additionally ensure we
never sleep in the init function if non-zero preempt_count or
interrupts are disabled as can happen in a slab cache ctor/dtor.
- Other minor formating fixes and such.
TODO:
- Finish the vmem memory allocation tracking
- Vet all other SPL primatives for potential sleeping during *_init. I
suspect the rwlock implemenation does this and should be fixes just
like the mutex implemenation.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@95 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
configurable number of threads like the Solaris version and almost
all of the options are supported. Unfortunately, it appears to have
made absolutely no difference to our performance numbers. I need
to keep looking for where we are bottle necking.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@93 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
function just to be extra safety and paranoid.
- Rewrite the thread shim to take full advantage of the
new kernel kthread API. This greatly simplifies things.
- Add a new regression test for thread_exit() to ensure
it properly terminates a thread immediately without
allowing futher execution of the thread.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@69 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
- Ensure we have at least 1 write-only splat test
- Fix return codes for vn_* Solaris does not use negative return
codes in the kernel. So linux errno's must be inverted.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@67 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
what I would call effecient but it does have the advantage
of being correct which is all I need right now. I added
a regression test as well.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@57 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
This should handle the absolute minimum I need for ZFS. It will
register the chdev with the right callbacks. Then the generic
registered linux callback will find the right registered solaris
callback for the function and munge the args just right before
passing it on. Should work, but untested (just compiled), so I
expect bugs.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@52 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
stuff which only inclused the getf()/releasef() in to the vnode area
where it will only really be used. These calls allow a user to
grab an open file struct given only the known open fd for a particular
user context. ZFS makes use of these, but they're a bit tricky to
test from within the kernel since you already need the file open
and know the fd. So we basically spook the system calls to setup
the environment we need for the splat test case and verify given
just the know fd we can get the file, create the needed vnode, and
then use the vnode interface as usual to read and write from it.
While I was hacking away I also noticed a NULL termination issue
in the second kobj test case so I fixed that too. In fact, I fixed
a few other things as well but all for the best!
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@51 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
Adjust kmem slab interface to make a copy of the slab name before
passing it on to the linux slab (we free it latter too)
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@47 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
- Re-implmented kobj support based on the vnode support.
- Add TESTS option to check.sh, and removed delay after module load.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@39 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
Update check.sh script to take V=1 env var so you can run it verbosely as
follows if your chasing something: sudo make check V=1
Add new kobj api and needed regression tests to allow reading of files from
within the kernel. Normally thats not something I support but the spa layer
needs the support for its config file.
Add some more missing stub headers
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@38 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
Add sloopy atomic declaration which will need to be fixed (eventually)
Fill out more of the Solaris VM hooks
Adjust the create_thread function
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@26 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
muck with #includes in existing Solaris style source to get it
to find the right stuff.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@18 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
We've dropped all the linux- prefixes on the file in favor of spl-
which makes more sense. And we've cleaned up some of the includes
so everybody should be including their own dependencies properly.
All a module which wants to use the spl support needs to do in
include spl.h and ensure it has access to Module.symvers.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@16 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
- Removed all references to kzt and replaced with splat
- Moved portions of include files which do not need to be
available to all source files in to local.h files in
proper source subdirs.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@14 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
the directories at the top level but that proved troublesome. The
kernel buildsystem and autoconf were conflicting too much. To
resolve the issue I moved the kernel bits in to a modules directory
which can then only use the kernel build system. We just pass
along the likely make targets to the kernel build system.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@11 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
