FreeBSD Bugzilla – Attachment 146861 Details for
Bug 187594
[zfs] [patch] ZFS ARC behavior problem and fix
Home
|
New
|
Browse
|
Search
|
[?]
|
Reports
|
Help
|
New Account
|
Log In
Remember
[x]
|
Forgot Password
Login:
[x]
[patch]
arc reclam refactor (against head)
arc-reclaim-head.patch (text/plain), 9.06 KB, created by
Steven Hartland
on 2014-09-05 11:46:32 UTC
(
hide
)
Description:
arc reclam refactor (against head)
Filename:
MIME Type:
Creator:
Steven Hartland
Created:
2014-09-05 11:46:32 UTC
Size:
9.06 KB
patch
obsolete
>Index: sys/cddl/compat/opensolaris/kern/opensolaris_kmem.c >=================================================================== >--- sys/cddl/compat/opensolaris/kern/opensolaris_kmem.c (revision 270875) >+++ sys/cddl/compat/opensolaris/kern/opensolaris_kmem.c (working copy) >@@ -126,42 +126,6 @@ kmem_size_init(void *unused __unused) > } > SYSINIT(kmem_size_init, SI_SUB_KMEM, SI_ORDER_ANY, kmem_size_init, NULL); > >-/* >- * The return values from kmem_free_* are only valid once the pagedaemon >- * has been initialised, before then they return 0. >- * >- * To ensure the returns are valid the caller can use a SYSINIT with >- * subsystem set to SI_SUB_KTHREAD_PAGE and an order of at least >- * SI_ORDER_SECOND. >- */ >-u_int >-kmem_free_target(void) >-{ >- >- return (vm_cnt.v_free_target); >-} >- >-u_int >-kmem_free_min(void) >-{ >- >- return (vm_cnt.v_free_min); >-} >- >-u_int >-kmem_free_count(void) >-{ >- >- return (vm_cnt.v_free_count + vm_cnt.v_cache_count); >-} >- >-u_int >-kmem_page_count(void) >-{ >- >- return (vm_cnt.v_page_count); >-} >- > uint64_t > kmem_size(void) > { >@@ -169,13 +133,6 @@ kmem_size(void) > return (kmem_size_val); > } > >-uint64_t >-kmem_used(void) >-{ >- >- return (vmem_size(kmem_arena, VMEM_ALLOC)); >-} >- > static int > kmem_std_constructor(void *mem, int size __unused, void *private, int flags) > { >Index: sys/cddl/compat/opensolaris/sys/kmem.h >=================================================================== >--- sys/cddl/compat/opensolaris/sys/kmem.h (revision 270875) >+++ sys/cddl/compat/opensolaris/sys/kmem.h (working copy) >@@ -66,17 +66,6 @@ typedef struct kmem_cache { > void *zfs_kmem_alloc(size_t size, int kmflags); > void zfs_kmem_free(void *buf, size_t size); > uint64_t kmem_size(void); >-uint64_t kmem_used(void); >-u_int kmem_page_count(void); >- >-/* >- * The return values from kmem_free_* are only valid once the pagedaemon >- * has been initialised, before then they return 0. >- */ >-u_int kmem_free_count(void); >-u_int kmem_free_target(void); >-u_int kmem_free_min(void); >- > kmem_cache_t *kmem_cache_create(char *name, size_t bufsize, size_t align, > int (*constructor)(void *, void *, int), void (*destructor)(void *, void *), > void (*reclaim)(void *) __unused, void *private, vmem_t *vmp, int cflags); >@@ -88,6 +77,9 @@ void kmem_reap(void); > int kmem_debugging(void); > void *calloc(size_t n, size_t s); > >+#define freemem (vm_cnt.v_free_count + vm_cnt.v_cache_count) >+#define minfree vm_cnt.v_free_min >+#define heap_arena kmem_arena > #define kmem_alloc(size, kmflags) zfs_kmem_alloc((size), (kmflags)) > #define kmem_zalloc(size, kmflags) zfs_kmem_alloc((size), (kmflags) | M_ZERO) > #define kmem_free(buf, size) zfs_kmem_free((buf), (size)) >Index: sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c >=================================================================== >--- sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c (revision 270875) >+++ sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c (working copy) >@@ -138,6 +138,7 @@ > #include <sys/sdt.h> > > #include <vm/vm_pageout.h> >+#include <machine/vmparam.h> > > #ifdef illumos > #ifndef _KERNEL >@@ -201,7 +202,7 @@ int zfs_arc_shrink_shift = 0; > int zfs_arc_p_min_shift = 0; > int zfs_disable_dup_eviction = 0; > uint64_t zfs_arc_average_blocksize = 8 * 1024; /* 8KB */ >-u_int zfs_arc_free_target = (1 << 19); /* default before pagedaemon init only */ >+u_int zfs_arc_free_target = (1 << 16); /* default before pagedaemon init only */ > > static int sysctl_vfs_zfs_arc_free_target(SYSCTL_HANDLER_ARGS); > >@@ -210,11 +211,10 @@ static void > arc_free_target_init(void *unused __unused) > { > >- zfs_arc_free_target = kmem_free_target(); >+ zfs_arc_free_target = vm_pageout_wakeup_thresh; > } > SYSINIT(arc_free_target_init, SI_SUB_KTHREAD_PAGE, SI_ORDER_ANY, > arc_free_target_init, NULL); >-#endif > > TUNABLE_QUAD("vfs.zfs.arc_meta_limit", &zfs_arc_meta_limit); > SYSCTL_DECL(_vfs_zfs); >@@ -245,9 +245,9 @@ sysctl_vfs_zfs_arc_free_target(SYSCTL_HANDLER_ARGS > if (err != 0 || req->newptr == NULL) > return (err); > >- if (val < kmem_free_min()) >+ if (val < minfree) > return (EINVAL); >- if (val > kmem_page_count()) >+ if (val > vm_cnt.v_page_count) > return (EINVAL); > > zfs_arc_free_target = val; >@@ -254,6 +254,7 @@ sysctl_vfs_zfs_arc_free_target(SYSCTL_HANDLER_ARGS > > return (0); > } >+#endif > > /* > * Note that buffers can be in one of 6 states: >@@ -2503,18 +2504,13 @@ arc_reclaim_needed(void) > return (1); > } > >- if (kmem_free_count() < zfs_arc_free_target) { >- DTRACE_PROBE2(arc__reclaim_freetarget, uint64_t, >- kmem_free_count(), uint64_t, zfs_arc_free_target); >- return (1); >- } >- > /* > * Cooperate with pagedaemon when it's time for it to scan > * and reclaim some pages. > */ >- if (vm_paging_needed()) { >- DTRACE_PROBE(arc__reclaim_paging); >+ if (freemem < zfs_arc_free_target) { >+ DTRACE_PROBE2(arc__reclaim_freemem, uint64_t, >+ freemem, uint64_t, zfs_arc_free_target); > return (1); > } > >@@ -2544,8 +2540,19 @@ arc_reclaim_needed(void) > if (availrmem < swapfs_minfree + swapfs_reserve + extra) > return (1); > >-#if defined(__i386) > /* >+ * Check that we have enough availrmem that memory locking (e.g., via >+ * mlock(3C) or memcntl(2)) can still succeed. (pages_pp_maximum >+ * stores the number of pages that cannot be locked; when availrmem >+ * drops below pages_pp_maximum, page locking mechanisms such as >+ * page_pp_lock() will fail.) >+ */ >+ if (availrmem <= pages_pp_maximum) >+ return (1); >+ >+#endif /* sun */ >+#if defined(__i386) || !defined(UMA_MD_SMALL_ALLOC) >+ /* > * If we're on an i386 platform, it's possible that we'll exhaust the > * kernel heap space before we ever run out of available physical > * memory. Most checks of the size of the heap_area compare against >@@ -2556,25 +2563,33 @@ arc_reclaim_needed(void) > * heap is allocated. (Or, in the calculation, if less than 1/4th is > * free) > */ >- if (btop(vmem_size(heap_arena, VMEM_FREE)) < >- (btop(vmem_size(heap_arena, VMEM_FREE | VMEM_ALLOC)) >> 2)) >- return (1); >-#endif >-#else /* sun */ >-#ifdef __i386__ >- /* i386 has KVA limits that the raw page counts above don't consider */ >- if (kmem_used() > (kmem_size() * 3) / 4) { >+ if (vmem_size(heap_arena, VMEM_FREE) < >+ (vmem_size(heap_arena, VMEM_FREE | VMEM_ALLOC) >> 2)) { > DTRACE_PROBE2(arc__reclaim_used, uint64_t, >- kmem_used(), uint64_t, (kmem_size() * 3) / 4); >+ vmem_size(heap_arena, VMEM_FREE), uint64_t, >+ (vmem_size(heap_arena, VMEM_FREE | VMEM_ALLOC)) >> 2); > return (1); > } > #endif >+#ifdef sun >+ /* >+ * If zio data pages are being allocated out of a separate heap segment, >+ * then enforce that the size of available vmem for this arena remains >+ * above about 1/16th free. >+ * >+ * Note: The 1/16th arena free requirement was put in place >+ * to aggressively evict memory from the arc in order to avoid >+ * memory fragmentation issues. >+ */ >+ if (zio_arena != NULL && >+ vmem_size(zio_arena, VMEM_FREE) < >+ (vmem_size(zio_arena, VMEM_ALLOC) >> 4)) >+ return (1); > #endif /* sun */ >- >-#else >+#else /* _KERNEL */ > if (spa_get_random(100) == 0) > return (1); >-#endif >+#endif /* _KERNEL */ > DTRACE_PROBE(arc__reclaim_no); > > return (0); >@@ -2625,6 +2640,15 @@ arc_kmem_reap_now(arc_reclaim_strategy_t strat) > } > kmem_cache_reap_now(buf_cache); > kmem_cache_reap_now(hdr_cache); >+ >+#ifdef sun >+ /* >+ * Ask the vmem areana to reclaim unused memory from its >+ * quantum caches. >+ */ >+ if (zio_arena != NULL && strat == ARC_RECLAIM_AGGR) >+ vmem_qcache_reap(zio_arena); >+#endif > } > > static void >@@ -2774,20 +2798,6 @@ arc_evict_needed(arc_buf_contents_t type) > if (type == ARC_BUFC_METADATA && arc_meta_used >= arc_meta_limit) > return (1); > >-#ifdef sun >-#ifdef _KERNEL >- /* >- * If zio data pages are being allocated out of a separate heap segment, >- * then enforce that the size of available vmem for this area remains >- * above about 1/32nd free. >- */ >- if (type == ARC_BUFC_DATA && zio_arena != NULL && >- vmem_size(zio_arena, VMEM_FREE) < >- (vmem_size(zio_arena, VMEM_ALLOC) >> 5)) >- return (1); >-#endif >-#endif /* sun */ >- > if (arc_reclaim_needed()) > return (1); > >@@ -3946,20 +3956,16 @@ static int > arc_memory_throttle(uint64_t reserve, uint64_t txg) > { > #ifdef _KERNEL >- uint64_t available_memory = >- ptoa((uintmax_t)vm_cnt.v_free_count + vm_cnt.v_cache_count); >+ uint64_t available_memory = ptob(freemem); > static uint64_t page_load = 0; > static uint64_t last_txg = 0; > >-#ifdef sun >-#if defined(__i386) >+#if defined(__i386) || !defined(UMA_MD_SMALL_ALLOC) > available_memory = >- MIN(available_memory, vmem_size(heap_arena, VMEM_FREE)); >+ MIN(available_memory, ptob(vmem_size(heap_arena, VMEM_FREE))); > #endif >-#endif /* sun */ > >- if (vm_cnt.v_free_count + vm_cnt.v_cache_count > >- (uint64_t)physmem * arc_lotsfree_percent / 100) >+ if (freemem > (uint64_t)physmem * arc_lotsfree_percent / 100) > return (0); > > if (txg > last_txg) { >@@ -3972,7 +3978,7 @@ arc_memory_throttle(uint64_t reserve, uint64_t txg > * continue to let page writes occur as quickly as possible. > */ > if (curproc == pageproc) { >- if (page_load > available_memory / 4) >+ if (page_load > MAX(ptob(minfree), available_memory) / 4) > return (SET_ERROR(ERESTART)); > /* Note: reserve is inflated, so we deflate */ > page_load += reserve / 8;
You cannot view the attachment while viewing its details because your browser does not support IFRAMEs.
View the attachment on a separate page
.
View Attachment As Diff
View Attachment As Raw
Actions:
View
|
Diff
Attachments on
bug 187594
:
140882
|
140883
|
140884
|
140885
|
140886
|
140887
|
140888
|
140889
|
140890
|
140891
|
140892
|
146178
|
146203
|
146249
|
146251
|
146287
|
146300
|
146373
|
146423
|
146424
|
146456
|
146816
|
146817
|
146851
|
146852
|
146854
|
146859
|
146861
|
146946
|
146947
|
146948
|
146949
|
147014
|
147068
|
147069
|
147070
|
147265
|
147274
|
147275
|
147276
|
147286
|
147459
|
147607
|
147609
|
147733
|
147738
|
147754
|
147815
|
152852
|
158809
|
159207
|
159688
|
159859
|
159905
|
161691
|
161692
|
161943
|
164051
|
174197
|
174198
|
174231
|
174232
|
174254
|
186818