From 27af7d6ea5015e5ef1f7985eab94a8a218267a2b Mon Sep 17 00:00:00 2001 From: ChenLiang Date: Mon, 24 Nov 2014 19:55:47 +0800 Subject: xbzrle: optimize XBZRLE to decrease the cache misses 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 include 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 Signed-off-by: Gonglei Reviewed-by: Eric Blake Signed-off-by: Amit Shah --- include/migration/page_cache.h | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/migration/page_cache.h b/include/migration/page_cache.h index 2d5ce2dd7a..10ed53274c 100644 --- a/include/migration/page_cache.h +++ b/include/migration/page_cache.h @@ -43,8 +43,10 @@ void cache_fini(PageCache *cache); * * @cache pointer to the PageCache struct * @addr: page addr + * @current_age: current bitmap generation */ -bool cache_is_cached(const PageCache *cache, uint64_t addr); +bool cache_is_cached(const PageCache *cache, uint64_t addr, + uint64_t current_age); /** * get_cached_data: Get the data cached for an addr @@ -60,13 +62,15 @@ uint8_t *get_cached_data(const PageCache *cache, uint64_t addr); * cache_insert: insert the page into the cache. the page cache * will dup the data on insert. the previous value will be overwritten * - * Returns -1 on error + * Returns -1 when the page isn't inserted into cache * * @cache pointer to the PageCache struct * @addr: page address * @pdata: pointer to the page + * @current_age: current bitmap generation */ -int cache_insert(PageCache *cache, uint64_t addr, const uint8_t *pdata); +int cache_insert(PageCache *cache, uint64_t addr, const uint8_t *pdata, + uint64_t current_age); /** * cache_resize: resize the page cache. In case of size reduction the extra -- cgit v1.2.3-55-g7522 From e1a8c9b67fc97d293211773edcae9e8e2f3367ab Mon Sep 17 00:00:00 2001 From: Dr. David Alan Gilbert Date: Thu, 8 Jan 2015 11:11:30 +0000 Subject: socket shutdown Add QEMUFile interface to allow a socket to be 'shut down' - i.e. any reads/writes will fail (and any blocking read/write will be woken). Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Paolo Bonzini Reviewed-by: Amit Shah Signed-off-by: Amit Shah --- include/migration/qemu-file.h | 10 ++++++++++ include/qemu/sockets.h | 7 +++++++ migration/qemu-file-unix.c | 23 +++++++++++++++++++---- migration/qemu-file.c | 12 ++++++++++++ 4 files changed, 48 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h index 401676bf4d..d843c0010c 100644 --- a/include/migration/qemu-file.h +++ b/include/migration/qemu-file.h @@ -84,6 +84,14 @@ typedef size_t (QEMURamSaveFunc)(QEMUFile *f, void *opaque, size_t size, int *bytes_sent); +/* + * Stop any read or write (depending on flags) on the underlying + * transport on the QEMUFile. + * Existing blocking reads/writes must be woken + * Returns 0 on success, -err on error + */ +typedef int (QEMUFileShutdownFunc)(void *opaque, bool rd, bool wr); + typedef struct QEMUFileOps { QEMUFilePutBufferFunc *put_buffer; QEMUFileGetBufferFunc *get_buffer; @@ -94,6 +102,7 @@ typedef struct QEMUFileOps { QEMURamHookFunc *after_ram_iterate; QEMURamHookFunc *hook_ram_load; QEMURamSaveFunc *save_page; + QEMUFileShutdownFunc *shut_down; } QEMUFileOps; struct QEMUSizedBuffer { @@ -177,6 +186,7 @@ void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate); int64_t qemu_file_get_rate_limit(QEMUFile *f); int qemu_file_get_error(QEMUFile *f); void qemu_file_set_error(QEMUFile *f, int ret); +int qemu_file_shutdown(QEMUFile *f); void qemu_fflush(QEMUFile *f); static inline void qemu_put_be64s(QEMUFile *f, const uint64_t *pv) diff --git a/include/qemu/sockets.h b/include/qemu/sockets.h index f47dae614a..7992ece72a 100644 --- a/include/qemu/sockets.h +++ b/include/qemu/sockets.h @@ -44,6 +44,13 @@ int socket_set_fast_reuse(int fd); int send_all(int fd, const void *buf, int len1); int recv_all(int fd, void *buf, int len1, bool single_read); +#ifdef WIN32 +/* Windows has different names for the same constants with the same values */ +#define SHUT_RD 0 +#define SHUT_WR 1 +#define SHUT_RDWR 2 +#endif + /* callback function for nonblocking connect * valid fd on success, negative error code on failure */ diff --git a/migration/qemu-file-unix.c b/migration/qemu-file-unix.c index 9682396d97..bfbc0861ab 100644 --- a/migration/qemu-file-unix.c +++ b/migration/qemu-file-unix.c @@ -26,6 +26,7 @@ #include "qemu/sockets.h" #include "block/coroutine.h" #include "migration/qemu-file.h" +#include "migration/qemu-file-internal.h" typedef struct QEMUFileSocket { int fd; @@ -84,6 +85,17 @@ static int socket_close(void *opaque) return 0; } +static int socket_shutdown(void *opaque, bool rd, bool wr) +{ + QEMUFileSocket *s = opaque; + + if (shutdown(s->fd, rd ? (wr ? SHUT_RDWR : SHUT_RD) : SHUT_WR)) { + return -errno; + } else { + return 0; + } +} + static ssize_t unix_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, int64_t pos) { @@ -192,15 +204,18 @@ QEMUFile *qemu_fdopen(int fd, const char *mode) } static const QEMUFileOps socket_read_ops = { - .get_fd = socket_get_fd, + .get_fd = socket_get_fd, .get_buffer = socket_get_buffer, - .close = socket_close + .close = socket_close, + .shut_down = socket_shutdown + }; static const QEMUFileOps socket_write_ops = { - .get_fd = socket_get_fd, + .get_fd = socket_get_fd, .writev_buffer = socket_writev_buffer, - .close = socket_close + .close = socket_close, + .shut_down = socket_shutdown }; QEMUFile *qemu_fopen_socket(int fd, const char *mode) diff --git a/migration/qemu-file.c b/migration/qemu-file.c index a7f2a34430..edc283073a 100644 --- a/migration/qemu-file.c +++ b/migration/qemu-file.c @@ -30,6 +30,18 @@ #include "migration/qemu-file-internal.h" #include "trace.h" +/* + * Stop a file from being read/written - not all backing files can do this + * typically only sockets can. + */ +int qemu_file_shutdown(QEMUFile *f) +{ + if (!f->ops->shut_down) { + return -ENOSYS; + } + return f->ops->shut_down(f->opaque, true, true); +} + bool qemu_file_mode_is_not_valid(const char *mode) { if (mode == NULL || -- cgit v1.2.3-55-g7522 From ea987c2c21d4326bb58ee28f6888fdcf8fbda067 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 7 Jan 2015 15:12:13 +0100 Subject: vmstate: type-check sub-arrays While we cannot check against the type of the full array, we can check against the type of the fields. Signed-off-by: Paolo Bonzini Signed-off-by: Amit Shah --- include/migration/vmstate.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index e45fc49cb1..d712a651ca 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -189,7 +189,7 @@ extern const VMStateInfo vmstate_info_bitmap; type_check_2darray(_type, typeof_field(_state, _field), _n1, _n2)) #define vmstate_offset_sub_array(_state, _field, _type, _start) \ - (offsetof(_state, _field[_start])) + vmstate_offset_value(_state, _field[_start], _type) #define vmstate_offset_buffer(_state, _field) \ vmstate_offset_array(_state, _field, uint8_t, \ -- cgit v1.2.3-55-g7522