causing poor interactive performance while unnice processes were running.
The new scheme still allows nice to have an effect on priority but it is
not as dramatic as the effect of the interactivity score.
before calling it for bound thread. To avoid this problem, change
thread_schedule_upcall to not put new thread on run queue, let caller
do it, so we can tweak the new thread before setting it to run.
Reported by: pho
threads in the process have already masked the signal, so job control
is delayed. But later a thread unmasking the STOP signal should enable
job control, so in issignal(), scanning all threads in process to see
if we can direct suspend some of them, not just suspend current thread.
we can deadlock because of lock order reversals. This was not
caught because Witness ignores pool mutexes right now.
Diagnosis and help: truckman
Noticed by: pho
"maxproc limit exceeded by uid %i, please see tuning(7) and login.conf(5)."
Which will be triggered whenever a user hits his/her maxproc limit or
the systemwide maxproc limit is reached.
MFC after: 1 week
mutexes are supposed to only be used as leaf mutexes, and what appear
to be separate pool mutexes could be aliased together, it is bad idea
for a thread to attempt to hold two pool mutexes at the same time.
Slightly rearrange the code in kern_open() so that FILE_UNLOCK() is
called before calling VOP_GETVOBJECT(), which will grab the v_vnlock
mutex.
systems to fail more gracefully when a file descriptor exhaustion situation
occurs.
Original patch by: David G. Andersen <dga@lcs.mit.edu>
PR: 45353
MFC after: 1 week
because the run time exceeds the largest value a signed int can hold.
The real solution involves calculating how far we are over the limit.
To quickly solve this problem we loop removing 1/5th of the current value
until it falls below the limit. The common case requires no passes.
and run time.
- Scale the sleep and run time back via sched_interact_update() in more
places. This is to keep the statistic more accurate.
- Charge a parent one tick for forking a child.
- Add only the run time and not the sleep time to the parents kg when a
thread exits. This allows us to give a penalty for having an expensive
thread exit but does not give a bonus for having an interactive thread
exit.
- Change the SLP_RUN_THROTTLE to limit us to 4/5th and not 1/2.
- Change the SLP_RUN_MAX to two seconds. This keeps bursty interactive
applications like mozilla and openoffice in the interactive range even
through expensive tasks.
- Recalculate the slice after every sleep. This ensures that once a task
has been marked interactive it only has a slice of 1 at the risk of
giving tasks that sleep for a very brief period a longer time slice.
schedules an upcall. Signal delivering to a bound thread is same as
non-threaded process. This is intended to be used by libpthread to
implement PTHREAD_SCOPE_SYSTEM thread.
2. Simplify kse_release() a bit, remove sleep loop.
panics. Before revision 1.38, we used to just point panicstr at the
format string if panicstr was NULL, but since we now use a static
buffer for the formatted panic message, we have to be careful to
only write to it during the first panic.
Pointed out by: bde
which meant no process would run for longer than 20ms.
- Slightly redo the interactivity scorer. It follows the same algorithm but
in a slightly more correct way. Previously values above half were
incorrect.
- Lower the interactivity threshold to 20. It seems that in testing non-
interactive tasks are hardly ever near there and expensive interactive
tasks can sometimes surpass it. This area needs more testing.
- Remove an unnecessary KTR.
- Fix a case where an idle thread that had an elevated priority due to
priority prop. would be placed back on the idle queue.
- Delay setting NEEDRESCHED until userret() for threads that haad their
priority elevated while in kernel. This gives us the same context switch
optimization as SCHED_4BSD.
- Limit the child's slice to 1 in sched_fork_kse() so we detect its behavior
more quickly.
- Inhert some of the run/slp time from the child in sched_exit_ksegrp().
- Redo some of the priority comparisons so they are more clear.
- Throttle the frequency of sched_pctcpu_update() so that rounding errors
do not make it invalid.
to the machine-independent parts of the VM. At the same time, this
introduces vm object locking for the non-i386 platforms.
Two details:
1. KSTACK_GUARD has been removed in favor of KSTACK_GUARD_PAGES. The
different machine-dependent implementations used various combinations
of KSTACK_GUARD and KSTACK_GUARD_PAGES. To disable guard page, set
KSTACK_GUARD_PAGES to 0.
2. Remove the (unnecessary) clearing of PG_ZERO in vm_thread_new. In
5.x, (but not 4.x,) PG_ZERO can only be set if VM_ALLOC_ZERO is passed
to vm_page_alloc() or vm_page_grab().
small but noticeable increase in performance for name lookup operations.
The code uses two zones, one for short names (less than 32 characters)
and one for long names (up to NAME_MAX). Since most file names are
fairly short, this saves a considerable amount of space that would
otherwise be wasted if we always allocated NAME_MAX bytes. The cutoff
value of 32 characters was picked arbitrarily and may benefit from some
tweaking; it could also be made into a tunable.
Submitted by: hmp
too small panics on PAE machines which have odd > 4GB sizes (4.5 gig
would render a 20MB of KVA for kmem_map instead of 200MB).
Submitted by: John Cagle <john.cagle@hp.com>, jeff
Reviewed by: jeff, peter, scottl, lots of USENIX folks
