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2015-01-15xbzrle: rebuild the cache_is_cached functionChenLiang
Rebuild the cache_is_cached function by cache_get_by_addr. And drops the asserts because the caller is also asserting the same thing. Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
2015-01-15xbzrle: optimize XBZRLE to decrease the cache missesChenLiang
Avoid hot pages being replaced by others to remarkably decrease cache misses Sample results with the test program which quote from xbzrle.txt ran in vm:(migrate bandwidth:1GE and xbzrle cache size 8MB) the test program: include <stdlib.h> include <stdio.h> int main() { char *buf = (char *) calloc(4096, 4096); while (1) { int i; for (i = 0; i < 4096 * 4; i++) { buf[i * 4096 / 4]++; } printf("."); } } before this patch: virsh qemu-monitor-command test_vm '{"execute": "query-migrate"}' {"return":{"expected-downtime":1020,"xbzrle-cache":{"bytes":1108284, "cache-size":8388608,"cache-miss-rate":0.987013,"pages":18297,"overflow":8, "cache-miss":1228737},"status":"active","setup-time":10,"total-time":52398, "ram":{"total":12466991104,"remaining":1695744,"mbps":935.559472, "transferred":5780760580,"dirty-sync-counter":271,"duplicate":2878530, "dirty-pages-rate":29130,"skipped":0,"normal-bytes":5748592640, "normal":1403465}},"id":"libvirt-706"} 18k pages sent compressed in 52 seconds. cache-miss-rate is 98.7%, totally miss. after optimizing: virsh qemu-monitor-command test_vm '{"execute": "query-migrate"}' {"return":{"expected-downtime":2054,"xbzrle-cache":{"bytes":5066763, "cache-size":8388608,"cache-miss-rate":0.485924,"pages":194823,"overflow":0, "cache-miss":210653},"status":"active","setup-time":11,"total-time":18729, "ram":{"total":12466991104,"remaining":3895296,"mbps":937.663549, "transferred":1615042219,"dirty-sync-counter":98,"duplicate":2869840, "dirty-pages-rate":58781,"skipped":0,"normal-bytes":1588404224, "normal":387794}},"id":"libvirt-266"} 194k pages sent compressed in 18 seconds. The value of cache-miss-rate decrease to 48.59%. Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
2014-06-10migration: Plug memory leak in migrate-set-cache-size commandChen Gang
We call g_free() after cache_fini() in migration_end(), but we don't call it after cache_fini() in xbzrle_cache_resize(), leaking the memory. cache_init() and cache_fini() are a pair. Since cache_init() allocates the cache, let cache_fini() free it. This plugs the leak. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-02-25Fix two XBZRLE corruption issuesDr. David Alan Gilbert
Push zero'd pages into the XBZRLE cache A page that was cached by XBZRLE, zero'd and then XBZRLE'd again was being compared against a stale cache value Don't use 'qemu_put_buffer_async' to put pages from the XBZRLE cache Since the cache might change before the data hits the wire Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-02-04Don't abort on memory allocation errorOrit Wasserman
It is better to fail migration in case of failure to allocate new cache item Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-02-04Don't abort on out of memory when creating page cacheOrit Wasserman
Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-05-18remove some double-includesMichael Tokarev
Some source files #include the same header more than once for no good reason. Remove second #includes in such cases. Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-03-11page_cache: dup memory on insertPeter Lieven
The page cache frees all data on finish, on resize and if there is collision on insert. So it should be the caches responsibility to dup the data that is stored in the cache. Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11page_cache: fix memory leakPeter Lieven
XBZRLE encoded migration introduced a MRU page cache meachnism. Unfortunately, cached items where never freed in case of a collision in the page cache on cache_insert(). This lead to out of memory conditions during XBZRLE migration if the page cache was small and there where a lot of collisions in the cache. Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11Fix cache_resize to keep old entry ageOrit Wasserman
Instead of using cache_insert do the update itself Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11Fix page_cache leak in cache_resizeOrit Wasserman
Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-12-19migration: move include files to include/migration/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-08-08Add cache handling functionsOrit Wasserman
Add MRU page cache mechanism. The page are accessed by their address. Signed-off-by: Benoit Hudzia <benoit.hudzia@sap.com> Signed-off-by: Petter Svard <petters@cs.umu.se> Signed-off-by: Aidan Shribman <aidan.shribman@sap.com> Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>