From patchwork Thu Sep 1 11:44:15 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhi Yong Wu X-Patchwork-Id: 112900 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 193C6B6F77 for ; Thu, 1 Sep 2011 22:03:17 +1000 (EST) Received: from localhost ([::1]:37028 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qz5z3-0000ov-Uy for incoming@patchwork.ozlabs.org; Thu, 01 Sep 2011 08:03:01 -0400 Received: from eggs.gnu.org ([140.186.70.92]:56687) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qz5yP-0006qS-D0 for qemu-devel@nongnu.org; Thu, 01 Sep 2011 08:02:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qz5ie-0003FY-DB for qemu-devel@nongnu.org; Thu, 01 Sep 2011 07:46:06 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:34420) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qz5ie-0003Bi-0p for qemu-devel@nongnu.org; Thu, 01 Sep 2011 07:46:04 -0400 Received: from d03relay05.boulder.ibm.com (d03relay05.boulder.ibm.com [9.17.195.107]) by e39.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id p81BUKGa004404 for ; Thu, 1 Sep 2011 05:30:20 -0600 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay05.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p81Bjf5g150464 for ; Thu, 1 Sep 2011 05:45:41 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p815jDw7025029 for ; Wed, 31 Aug 2011 23:45:14 -0600 Received: from us.ibm.com ([9.115.118.18]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with SMTP id p815j9DE023733; Wed, 31 Aug 2011 23:45:09 -0600 Received: by us.ibm.com (sSMTP sendmail emulation); Thu, 1 Sep 2011 19:45:21 +0800 From: Zhi Yong Wu To: qemu-devel@nongnu.org Date: Thu, 1 Sep 2011 19:44:15 +0800 Message-Id: <1314877456-19521-4-git-send-email-wuzhy@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.6 In-Reply-To: <1314877456-19521-1-git-send-email-wuzhy@linux.vnet.ibm.com> References: <1314877456-19521-1-git-send-email-wuzhy@linux.vnet.ibm.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-Received-From: 32.97.110.160 Cc: kwolf@redhat.com, aliguori@us.ibm.com, stefanha@linux.vnet.ibm.com, kvm@vger.kernel.org, mtosatti@redhat.com, Zhi Yong Wu , pair@us.ibm.com, zwu.kernel@gmail.com, ryanh@us.ibm.com Subject: [Qemu-devel] [PATCH v6 3/4] block: add block timer and block throttling algorithm X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Note: 1.) When bps/iops limits are specified to a small value such as 511 bytes/s, this VM will hang up. We are considering how to handle this senario. 2.) When "dd" command is issued in guest, if its option bs is set to a large value such as "bs=1024K", the result speed will slightly bigger than the limits. For these problems, if you have nice thought, pls let us know.:) Signed-off-by: Zhi Yong Wu --- block.c | 290 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-- block.h | 5 + block_int.h | 9 ++ 3 files changed, 296 insertions(+), 8 deletions(-) diff --git a/block.c b/block.c index 17ee3df..680f1e7 100644 --- a/block.c +++ b/block.c @@ -30,6 +30,9 @@ #include "qemu-objects.h" #include "qemu-coroutine.h" +#include "qemu-timer.h" +#include "block/blk-queue.h" + #ifdef CONFIG_BSD #include #include @@ -72,6 +75,13 @@ static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, QEMUIOVector *iov); static int coroutine_fn bdrv_co_flush_em(BlockDriverState *bs); +static bool bdrv_exceed_bps_limits(BlockDriverState *bs, int nb_sectors, + bool is_write, double elapsed_time, uint64_t *wait); +static bool bdrv_exceed_iops_limits(BlockDriverState *bs, bool is_write, + double elapsed_time, uint64_t *wait); +static bool bdrv_exceed_io_limits(BlockDriverState *bs, int nb_sectors, + bool is_write, uint64_t *wait); + static QTAILQ_HEAD(, BlockDriverState) bdrv_states = QTAILQ_HEAD_INITIALIZER(bdrv_states); @@ -104,6 +114,64 @@ int is_windows_drive(const char *filename) } #endif +/* throttling disk I/O limits */ +void bdrv_io_limits_disable(BlockDriverState *bs) +{ + bs->io_limits_enabled = false; + + if (bs->block_queue) { + qemu_block_queue_flush(bs->block_queue); + qemu_del_block_queue(bs->block_queue); + bs->block_queue = NULL; + } + + if (bs->block_timer) { + qemu_del_timer(bs->block_timer); + qemu_free_timer(bs->block_timer); + bs->block_timer = NULL; + } + + bs->slice_start[BLOCK_IO_LIMIT_READ] = 0; + bs->slice_start[BLOCK_IO_LIMIT_WRITE] = 0; + + bs->slice_end[BLOCK_IO_LIMIT_READ] = 0; + bs->slice_end[BLOCK_IO_LIMIT_WRITE] = 0; +} + +static void bdrv_block_timer(void *opaque) +{ + BlockDriverState *bs = opaque; + BlockQueue *queue = bs->block_queue; + + qemu_block_queue_flush(queue); +} + +void bdrv_io_limits_enable(BlockDriverState *bs) +{ + bs->block_queue = qemu_new_block_queue(); + bs->block_timer = qemu_new_timer_ns(vm_clock, bdrv_block_timer, bs); + + bs->slice_start[BLOCK_IO_LIMIT_READ] = qemu_get_clock_ns(vm_clock); + bs->slice_start[BLOCK_IO_LIMIT_WRITE] = + bs->slice_start[BLOCK_IO_LIMIT_READ]; + + bs->slice_end[BLOCK_IO_LIMIT_READ] = + bs->slice_start[BLOCK_IO_LIMIT_READ] + BLOCK_IO_SLICE_TIME; + bs->slice_end[BLOCK_IO_LIMIT_WRITE] = + bs->slice_end[BLOCK_IO_LIMIT_READ]; +} + +bool bdrv_io_limits_enabled(BlockDriverState *bs) +{ + BlockIOLimit *io_limits = &bs->io_limits; + return io_limits->bps[BLOCK_IO_LIMIT_READ] + || io_limits->bps[BLOCK_IO_LIMIT_WRITE] + || io_limits->bps[BLOCK_IO_LIMIT_TOTAL] + || io_limits->iops[BLOCK_IO_LIMIT_READ] + || io_limits->iops[BLOCK_IO_LIMIT_WRITE] + || io_limits->iops[BLOCK_IO_LIMIT_TOTAL]; +} + /* check if the path starts with ":" */ static int path_has_protocol(const char *path) { @@ -694,6 +762,11 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags, bs->change_cb(bs->change_opaque, CHANGE_MEDIA); } + /* throttling disk I/O limits */ + if (bs->io_limits_enabled) { + bdrv_io_limits_enable(bs); + } + return 0; unlink_and_fail: @@ -732,6 +805,18 @@ void bdrv_close(BlockDriverState *bs) if (bs->change_cb) bs->change_cb(bs->change_opaque, CHANGE_MEDIA); } + + /* throttling disk I/O limits */ + if (bs->block_queue) { + qemu_del_block_queue(bs->block_queue); + bs->block_queue = NULL; + } + + if (bs->block_timer) { + qemu_del_timer(bs->block_timer); + qemu_free_timer(bs->block_timer); + bs->block_timer = NULL; + } } void bdrv_close_all(void) @@ -2290,13 +2375,29 @@ BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num, BlockDriverCompletionFunc *cb, void *opaque) { BlockDriver *drv = bs->drv; + uint64_t wait_time = 0; + BlockDriverAIOCB *ret; trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque); - if (!drv) - return NULL; - if (bdrv_check_request(bs, sector_num, nb_sectors)) + if (!drv || bdrv_check_request(bs, sector_num, nb_sectors)) { return NULL; + } + + /* throttling disk read I/O */ + if (bs->io_limits_enabled) { + if (bdrv_exceed_io_limits(bs, nb_sectors, false, &wait_time)) { + ret = qemu_block_queue_enqueue(bs->block_queue, bs, bdrv_aio_readv, + sector_num, qiov, nb_sectors, cb, opaque); + qemu_mod_timer(bs->block_timer, + wait_time + qemu_get_clock_ns(vm_clock)); + return ret; + } + + bs->io_disps.bytes[BLOCK_IO_LIMIT_READ] += + (unsigned) nb_sectors * BDRV_SECTOR_SIZE; + bs->io_disps.ios[BLOCK_IO_LIMIT_READ]++; + } return drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors, cb, opaque); @@ -2345,15 +2446,14 @@ BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, BlockDriver *drv = bs->drv; BlockDriverAIOCB *ret; BlockCompleteData *blk_cb_data; + uint64_t wait_time = 0; trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque); - if (!drv) - return NULL; - if (bs->read_only) - return NULL; - if (bdrv_check_request(bs, sector_num, nb_sectors)) + if (!drv || bs->read_only + || bdrv_check_request(bs, sector_num, nb_sectors)) { return NULL; + } if (bs->dirty_bitmap) { blk_cb_data = blk_dirty_cb_alloc(bs, sector_num, nb_sectors, cb, @@ -2362,6 +2462,17 @@ BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, opaque = blk_cb_data; } + /* throttling disk write I/O */ + if (bs->io_limits_enabled) { + if (bdrv_exceed_io_limits(bs, nb_sectors, true, &wait_time)) { + ret = qemu_block_queue_enqueue(bs->block_queue, bs, bdrv_aio_writev, + sector_num, qiov, nb_sectors, cb, opaque); + qemu_mod_timer(bs->block_timer, + wait_time + qemu_get_clock_ns(vm_clock)); + return ret; + } + } + ret = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors, cb, opaque); @@ -2369,6 +2480,12 @@ BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, if (bs->wr_highest_sector < sector_num + nb_sectors - 1) { bs->wr_highest_sector = sector_num + nb_sectors - 1; } + + if (bs->io_limits_enabled) { + bs->io_disps.bytes[BLOCK_IO_LIMIT_WRITE] += + (unsigned) nb_sectors * BDRV_SECTOR_SIZE; + bs->io_disps.ios[BLOCK_IO_LIMIT_WRITE]++; + } } return ret; @@ -2633,6 +2750,163 @@ void bdrv_aio_cancel(BlockDriverAIOCB *acb) acb->pool->cancel(acb); } +static bool bdrv_exceed_bps_limits(BlockDriverState *bs, int nb_sectors, + bool is_write, double elapsed_time, uint64_t *wait) { + uint64_t bps_limit = 0; + double bytes_limit, bytes_disp, bytes_res; + double slice_time, wait_time; + + if (bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL]) { + bps_limit = bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL]; + } else if (bs->io_limits.bps[is_write]) { + bps_limit = bs->io_limits.bps[is_write]; + } else { + if (wait) { + *wait = 0; + } + + return false; + } + + slice_time = bs->slice_end[is_write] - bs->slice_start[is_write]; + slice_time /= (NANOSECONDS_PER_SECOND); + bytes_limit = bps_limit * slice_time; + bytes_disp = bs->io_disps.bytes[is_write]; + if (bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL]) { + bytes_disp += bs->io_disps.bytes[!is_write]; + } + + bytes_res = (unsigned) nb_sectors * BDRV_SECTOR_SIZE; + + if (bytes_disp + bytes_res <= bytes_limit) { + if (wait) { + *wait = 0; + } + + return false; + } + + /* Calc approx time to dispatch */ + wait_time = (bytes_disp + bytes_res) / bps_limit - elapsed_time; + + if (wait) { + *wait = wait_time * BLOCK_IO_SLICE_TIME * 10; + } + + return true; +} + +static bool bdrv_exceed_iops_limits(BlockDriverState *bs, bool is_write, + double elapsed_time, uint64_t *wait) { + uint64_t iops_limit = 0; + double ios_limit, ios_disp; + double slice_time, wait_time; + + if (bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]) { + iops_limit = bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]; + } else if (bs->io_limits.iops[is_write]) { + iops_limit = bs->io_limits.iops[is_write]; + } else { + if (wait) { + *wait = 0; + } + + return false; + } + + slice_time = bs->slice_end[is_write] - bs->slice_start[is_write]; + slice_time /= (NANOSECONDS_PER_SECOND); + ios_limit = iops_limit * slice_time; + ios_disp = bs->io_disps.ios[is_write]; + if (bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]) { + ios_disp += bs->io_disps.ios[!is_write]; + } + + if (ios_disp + 1 <= ios_limit) { + if (wait) { + *wait = 0; + } + + return false; + } + + /* Calc approx time to dispatch */ + wait_time = (ios_disp + 1) / iops_limit; + if (wait_time > elapsed_time) { + wait_time = wait_time - elapsed_time; + } else { + wait_time = 0; + } + + if (wait) { + *wait = wait_time * BLOCK_IO_SLICE_TIME * 10; + } + + return true; +} + +static bool bdrv_exceed_io_limits(BlockDriverState *bs, int nb_sectors, + bool is_write, uint64_t *wait) { + int64_t now; + uint64_t bps_wait = 0, iops_wait = 0, max_wait; + double elapsed_time; + int bps_ret, iops_ret; + + now = qemu_get_clock_ns(vm_clock); + if ((bs->slice_start[is_write] < now) + && (bs->slice_end[is_write] > now)) { + bs->slice_end[is_write] = now + BLOCK_IO_SLICE_TIME; + } else { + bs->slice_start[is_write] = now; + bs->slice_end[is_write] = now + BLOCK_IO_SLICE_TIME; + + bs->io_disps.bytes[is_write] = 0; + bs->io_disps.bytes[!is_write] = 0; + + bs->io_disps.ios[is_write] = 0; + bs->io_disps.ios[!is_write] = 0; + } + + /* If a limit was exceeded, immediately queue this request */ + if (qemu_block_queue_has_pending(bs->block_queue)) { + if (bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL] + || bs->io_limits.bps[is_write] || bs->io_limits.iops[is_write] + || bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]) { + if (wait) { + *wait = 0; + } + + return true; + } + } + + elapsed_time = now - bs->slice_start[is_write]; + elapsed_time /= (NANOSECONDS_PER_SECOND); + + bps_ret = bdrv_exceed_bps_limits(bs, nb_sectors, + is_write, elapsed_time, &bps_wait); + iops_ret = bdrv_exceed_iops_limits(bs, is_write, + elapsed_time, &iops_wait); + if (bps_ret || iops_ret) { + max_wait = bps_wait > iops_wait ? bps_wait : iops_wait; + if (wait) { + *wait = max_wait; + } + + now = qemu_get_clock_ns(vm_clock); + if (bs->slice_end[is_write] < now + max_wait) { + bs->slice_end[is_write] = now + max_wait; + } + + return true; + } + + if (wait) { + *wait = 0; + } + + return false; +} /**************************************************************/ /* async block device emulation */ diff --git a/block.h b/block.h index 3ac0b94..a3e69db 100644 --- a/block.h +++ b/block.h @@ -58,6 +58,11 @@ void bdrv_info(Monitor *mon, QObject **ret_data); void bdrv_stats_print(Monitor *mon, const QObject *data); void bdrv_info_stats(Monitor *mon, QObject **ret_data); +/* disk I/O throttling */ +void bdrv_io_limits_enable(BlockDriverState *bs); +void bdrv_io_limits_disable(BlockDriverState *bs); +bool bdrv_io_limits_enabled(BlockDriverState *bs); + void bdrv_init(void); void bdrv_init_with_whitelist(void); BlockDriver *bdrv_find_protocol(const char *filename); diff --git a/block_int.h b/block_int.h index e7bda5b..5d37277 100644 --- a/block_int.h +++ b/block_int.h @@ -202,6 +202,15 @@ struct BlockDriverState { void *sync_aiocb; + /* the time for latest disk I/O */ + int64_t slice_start[2]; + int64_t slice_end[2]; + BlockIOLimit io_limits; + BlockIODisp io_disps; + BlockQueue *block_queue; + QEMUTimer *block_timer; + bool io_limits_enabled; + /* I/O stats (display with "info blockstats"). */ uint64_t nr_bytes[BDRV_MAX_IOTYPE]; uint64_t nr_ops[BDRV_MAX_IOTYPE];