From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NUfI1-0002Nf-En for qemu-devel@nongnu.org; Tue, 12 Jan 2010 06:52:01 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NUfHw-0002LY-Jv for qemu-devel@nongnu.org; Tue, 12 Jan 2010 06:52:01 -0500 Received: from [199.232.76.173] (port=60874 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NUfHw-0002LS-Eq for qemu-devel@nongnu.org; Tue, 12 Jan 2010 06:51:56 -0500 Received: from mx20.gnu.org ([199.232.41.8]:1690) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1NUfHv-0001gs-Po for qemu-devel@nongnu.org; Tue, 12 Jan 2010 06:51:56 -0500 Received: from david.siemens.de ([192.35.17.14]) by mx20.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NUfGu-0000UH-40 for qemu-devel@nongnu.org; Tue, 12 Jan 2010 06:50:52 -0500 Message-ID: <4B4C6216.2090606@siemens.com> Date: Tue, 12 Jan 2010 12:50:46 +0100 From: Jan Kiszka MIME-Version: 1.0 References: <1263284833297-git-send-email-lirans@il.ibm.com> <12632848342235-git-send-email-lirans@il.ibm.com> <12632848343008-git-send-email-lirans@il.ibm.com> In-Reply-To: <12632848343008-git-send-email-lirans@il.ibm.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: [PATCH 2/4] Tranfer dirty blocks during iterative phase List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Liran Schour Cc: qemu-devel@nongnu.org Liran Schour wrote: > Start transfer dirty blocks during the iterative stage. That will > reduce the time that the guest will be suspended > > Signed-off-by: Liran Schour > --- > block-migration.c | 158 +++++++++++++++++++++++++++++++++++++++-------------- > 1 files changed, 116 insertions(+), 42 deletions(-) > > diff --git a/block-migration.c b/block-migration.c > index 6957909..90c84b1 100644 > --- a/block-migration.c > +++ b/block-migration.c > @@ -29,6 +29,7 @@ > #define MAX_BLOCKS_READ 10000 > #define BLOCKS_READ_CHANGE 100 > #define INITIAL_BLOCKS_READ 100 > +#define MAX_DIRTY_ITERATIONS 100 > > //#define DEBUG_BLK_MIGRATION > > @@ -45,6 +46,7 @@ typedef struct BlkMigDevState { > int bulk_completed; > int shared_base; > int64_t cur_sector; > + int64_t cur_dirty; > int64_t completed_sectors; > int64_t total_sectors; > int64_t dirty; > @@ -73,6 +75,7 @@ typedef struct BlkMigState { > int64_t total_sector_sum; > int prev_progress; > int bulk_completed; > + int dirty_iterations; > } BlkMigState; > > static BlkMigState block_mig_state; > @@ -221,6 +224,7 @@ static void init_blk_migration(Monitor *mon, QEMUFile *f) > block_mig_state.total_sector_sum = 0; > block_mig_state.prev_progress = -1; > block_mig_state.bulk_completed = 0; > + block_mig_state.dirty_iterations = 0; > > for (bs = bdrv_first; bs != NULL; bs = bs->next) { > if (bs->type == BDRV_TYPE_HD) { > @@ -285,39 +289,88 @@ static int blk_mig_save_bulked_block(Monitor *mon, QEMUFile *f) > return ret; > } > > -#define MAX_NUM_BLOCKS 4 > - > -static void blk_mig_save_dirty_blocks(Monitor *mon, QEMUFile *f) > +static void blk_mig_reset_dirty_curser(void) My translation help makes me believe that 'curser' is not what you intended call this thing. :) > { > BlkMigDevState *bmds; > - BlkMigBlock blk; > - int64_t sector; > + > + QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) { > + bmds->cur_dirty = 0; > + } > +} > > - blk.buf = qemu_malloc(BLOCK_SIZE); > +static int mig_save_device_dirty(Monitor *mon, QEMUFile *f, > + BlkMigDevState *bmds, int is_async) > +{ > + BlkMigBlock *blk; > + int64_t total_sectors = bmds->total_sectors; > + int64_t sector; > + int nr_sectors; > > - QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) { > - for (sector = 0; sector < bmds->cur_sector;) { > - if (bdrv_get_dirty(bmds->bs, sector)) { > - if (bdrv_read(bmds->bs, sector, blk.buf, > - BDRV_SECTORS_PER_DIRTY_CHUNK) < 0) { > - monitor_printf(mon, "Error reading sector %" PRId64 "\n", > - sector); > - qemu_file_set_error(f); > - qemu_free(blk.buf); > - return; > + for (sector = bmds->cur_dirty; sector < bmds->total_sectors;) { > + if (bdrv_get_dirty(bmds->bs, sector)) { > + > + if (total_sectors - sector < BDRV_SECTORS_PER_DIRTY_CHUNK) { > + nr_sectors = total_sectors - sector; > + } else { > + nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK; > + } > + blk = qemu_malloc(sizeof(BlkMigBlock)); > + blk->buf = qemu_malloc(BLOCK_SIZE); > + blk->bmds = bmds; > + blk->sector = sector; > + > + if(is_async) { > + blk->iov.iov_base = blk->buf; > + blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE; > + qemu_iovec_init_external(&blk->qiov, &blk->iov, 1); > + > + blk->aiocb = bdrv_aio_readv(bmds->bs, sector, &blk->qiov, > + nr_sectors, blk_mig_read_cb, blk); > + if (!blk->aiocb) { > + goto error; > } > - blk.bmds = bmds; > - blk.sector = sector; > - blk_send(f, &blk); > - > - bdrv_reset_dirty(bmds->bs, sector, > - BDRV_SECTORS_PER_DIRTY_CHUNK); > + block_mig_state.submitted++; > + } else { > + if (bdrv_read(bmds->bs, sector, blk->buf, > + nr_sectors) < 0) { > + goto error; > + } > + blk_send(f, blk); > + > + qemu_free(blk->buf); > + qemu_free(blk); > } > - sector += BDRV_SECTORS_PER_DIRTY_CHUNK; > + > + bdrv_reset_dirty(bmds->bs, sector, nr_sectors); > + break; > } > + sector += BDRV_SECTORS_PER_DIRTY_CHUNK; > + bmds->cur_dirty = sector; > } > + > + return (bmds->cur_dirty >= bmds->total_sectors); > + > + error: Please do not indent the label. > + monitor_printf(mon, "Error reading sector %" PRId64 "\n", sector); > + qemu_file_set_error(f); > + qemu_free(blk->buf); > + qemu_free(blk); > + return 0; > +} > + > +static int blk_mig_save_dirty_block(Monitor *mon, QEMUFile *f, int is_async) > +{ > + BlkMigDevState *bmds; > + int ret = 0; > > - qemu_free(blk.buf); > + QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) { > + if(mig_save_device_dirty(mon, f, bmds, is_async) == 0) { > + ret = 1; > + break; > + } > + } > + > + return ret; > } > > static void flush_blks(QEMUFile* f) > @@ -386,6 +439,8 @@ static void blk_mig_cleanup(Monitor *mon) > > static int block_save_live(Monitor *mon, QEMUFile *f, int stage, void *opaque) > { > + int dirty_iteration = 0; > + > dprintf("Enter save live stage %d submitted %d transferred %d\n", > stage, block_mig_state.submitted, block_mig_state.transferred); > > @@ -413,29 +468,48 @@ static int block_save_live(Monitor *mon, QEMUFile *f, int stage, void *opaque) > blk_mig_cleanup(mon); > return 0; > } > - > - /* control the rate of transfer */ > - while ((block_mig_state.submitted + > - block_mig_state.read_done) * BLOCK_SIZE < > - qemu_file_get_rate_limit(f)) { > - if (blk_mig_save_bulked_block(mon, f) == 0) { > - /* finish saving bulk on all devices */ > - block_mig_state.bulk_completed = 1; > - break; > + > + blk_mig_reset_dirty_curser(); > + > + if(stage == 2) { > + /* control the rate of transfer */ > + while ((block_mig_state.submitted + > + block_mig_state.read_done) * BLOCK_SIZE < > + qemu_file_get_rate_limit(f)) { > + if (block_mig_state.bulk_completed == 0) { > + /* first finish the bulk phase */ > + if (blk_mig_save_bulked_block(mon, f) == 0) { > + /* finish saving bulk on all devices */ > + block_mig_state.bulk_completed = 1; > + } > + } else if (block_mig_state.dirty_iterations < MAX_DIRTY_ITERATIONS) { > + if (dirty_iteration == 0) { > + /* increment dirty iteration only once per round */ > + dirty_iteration = 1; > + block_mig_state.dirty_iterations++; > + } > + if (blk_mig_save_dirty_block(mon, f, 1) == 0) { > + /* no more dirty blocks */ > + break; > + } > + } else { > + /* if we got here stop the loop */ > + break; > + } I did not yet get the purpose and effect of the iteration limitation. Can you help me? > + } > + > + flush_blks(f); > + > + if (qemu_file_has_error(f)) { > + blk_mig_cleanup(mon); > + return 0; > } > } > - > - flush_blks(f); > - > - if (qemu_file_has_error(f)) { > - blk_mig_cleanup(mon); > - return 0; > - } > - > + > if (stage == 3) { > /* we now for sure that save bulk is completed */ > > - blk_mig_save_dirty_blocks(mon, f); > + while(blk_mig_save_dirty_block(mon, f, 0) != 0); while (... > blk_mig_cleanup(mon); > > /* report completion */ Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux