- struct timeval time is gone
time.tv_sec -> time_second
- struct timeval mono_time is gone
mono_time.tv_sec -> time_uptime
- access to time via
{get,}{micro,nano,bin}time()
get* versions are fast but less precise
- support NTP nanokernel implementation (NTP API 4)
- further reading:
Timecounter Paper: http://phk.freebsd.dk/pubs/timecounter.pdf
NTP Nanokernel: http://www.eecis.udel.edu/~mills/ntp/html/kern.html
1: I can understand it, and
2: It works.
Notable externally-visible changes are that POOL_SUBPAGE now has to be a
compile-time constant, and that trying to initialise a pool whose objects are
larger than POOL_SUBPAGE automatically generates a pool that doesn't use
subpages.
NetBSD/acorn26 now boots multi-user again.
the time pool_get() calls pool_catchup(), pp has been free'd but it is still
in the "entered" state. The chain pool_catchup() -> pool_allocator_alloc()
-> pool_reclaim() on pp fails because pp is still in the "entered" state.
Call pr_leave() before calling calling pool_catchup() to avoid this.
Thanks for the excellent analysis!
- pool_allocator_alloc: drain ourselves as well,
so that pool_cache on us is drained as well.
- pool_cache_put_paddr: destruct objects if underlying pool is starved.
- pool_get: on kva starvation, wake up once a second and try again.
Fixes:
PR/32287: Processes hang in "mclpl"
PR/32330: shark kernel hangs under memory load.
the original code since if fullgroups was empty and partgroups wasn't, we
would not clean up partgroups (pointed out by yamt). Well, this one has
different semantics from the original, they are the correct ones I think..
split the single list of pool cache groups into three lists:
completely full, partially full, and completely empty.
use LIST instead of TAILQ where appropriate.
- Make the locking rules for pr_rmpage() sane, and don't modify fields
protected by the pool lock without actually holding it.
- Always defer freeing the pool page to the back-end allocator, to avoid
invoking the pool_allocator with the pool locked (which would violate
the pool_allocator -> pool locking order).
- Fix pool_reclaim() to not violate the pool_cache -> pool locking order
by using a trylock.
Reviewed by Chuq Silvers.
- don't use managed mappings/backing objects for wired memory allocations.
save some resources like pv_entry. also fix (most of) PR/27030.
- simplify kernel memory management API.
- simplify pmap bootstrap of some ports.
- some related cleanups.
if it's specified, don't use free items as storage for internal state.
so that we can use pools for non memory backed objects.
inspired from solaris's KMC_NOTOUCH.
to pool_init. Untouched pools are ones that either in arch-specific
code, or aren't initialiased during initial system startup.
Convert struct session, ucred and lockf to pools.
In addition to current one (i.e., don't wast so large part of the page),
- if the header fitsin the page without wasting any items, put it there.
- don't put the header in the page if it may consume rather big item.
For example, on i386, header is now allocated in the page for the pools
like fdescpl or sigapl, and allocated off the page for the pools like
buf1k or buf2k.
idle pool pages to be returned to the system immediately upon becoming
de-fragmented.
Also, in pool_do_put(), don't free back an idle page unless we are over
our minimum page claim.
(1) split the single list of pages allocated to a pool into three lists:
completely full, partially full, and completely empty.
there is no longer any need to traverse any list looking for a
certain type of page.
(2) replace the 8-element hash table for out-of-page page headers
with a splay tree.
these two changes (together with the recent enhancements to the wait code)
give us linear scaling for a fork+exit microbenchmark.
objects. Clients of the pool_cache API must consistently use
the "paddr" variants or not, otherwise behavior is undefined.
Enable this on Alpha, ARM, MIPS, and x86. Other platforms must
define POOL_VTOPHYS() in the appropriate manner in order to enable
the feature.
Part 1 of a series of simple patches contributed by Wasabi Systems
to improve network performance.
