From 86620aac3cdff44a7b1834f6cb0adc1b94c255b8 Mon Sep 17 00:00:00 2001 From: Ryan Ding Date: Thu, 1 Sep 2016 15:40:35 +0800 Subject: performance/write-behind: fix flush stuck by former failed writes the issue is happened in this case: assume a file is opened with fd1 and fd2. 1. some WRITE opto fd1 got error, they were add back to 'todo' queue because of those error. 2. fd2 closed, a FLUSH op is send to write-behind. 3. FLUSH can not be unwind because it's not a legal waiter for those failed write(as func __wb_request_waiting_on() say). and those failed WRITE also can not be ended if fd1 is not closed. fd2 stuck in close syscall. to resolve this issue, we can change the way we determine 2 requests is 'conflict': flush/fsync is not conflict with those write that is not belonged to them. so __wb_pick_winds() can wind the FLUSH op. below is some information when the stuck issue happen: glusterdump logs: [xlator.performance.write-behind.wb_inode] path=/ltp-F9eG0ZSOME/rw-buffered-16436 inode=0x7fdbe8039b9c window_conf=1048576 window_current=249856 transit-size=0 dontsync=0 [.WRITE] request-ptr=0x7fdbe8020200 refcount=1 wound=no generation-number=4 req->op_ret=-1 req->op_errno=116 sync-attempts=3 sync-in-progress=no size=131072 offset=1220608 lied=-1 append=0 fulfilled=0 go=0 [.WRITE] request-ptr=0x7fdbe8068c30 refcount=1 wound=no generation-number=5 req->op_ret=-1 req->op_errno=116 sync-attempts=2 sync-in-progress=no size=118784 offset=1351680 lied=-1 append=0 fulfilled=0 go=0 [.FLUSH] request-ptr=0x7fdbe8021cd0 refcount=1 wound=no generation-number=6 req->op_ret=0 req->op_errno=0 sync-attempts=0 gdb detail about above 3 requests: (gdb) print *((wb_request_t *)0x7fdbe8021cd0) $2 = {all = {next = 0x7fdbe803a608, prev = 0x7fdbe8068c30}, todo = {next = 0x7fdbe803a618, prev = 0x7fdbe8068c40}, lie = {next = 0x7fdbe8021cf0, prev = 0x7fdbe8021cf0}, winds = {next = 0x7fdbe8021d00, prev = 0x7fdbe8021d00}, unwinds = {next = 0x7fdbe8021d10, prev = 0x7fdbe8021d10}, wip = { next = 0x7fdbe8021d20, prev = 0x7fdbe8021d20}, stub = 0x7fdbe80224dc, write_size = 0, orig_size = 0, total_size = 0, op_ret = 0, op_errno = 0, refcount = 1, wb_inode = 0x7fdbe803a5f0, fop = GF_FOP_FLUSH, lk_owner = {len = 8, data = "W\322T\f\271\367y$", '\000' }, iobref = 0x0, gen = 6, fd = 0x7fdbe800f0dc, wind_count = 0, ordering = {size = 0, off = 0, append = 0, tempted = 0, lied = 0, fulfilled = 0, go = 0}} (gdb) print *((wb_request_t *)0x7fdbe8020200) $3 = {all = {next = 0x7fdbe8068c30, prev = 0x7fdbe803a608}, todo = {next = 0x7fdbe8068c40, prev = 0x7fdbe803a618}, lie = {next = 0x7fdbe8068c50, prev = 0x7fdbe803a628}, winds = {next = 0x7fdbe8020230, prev = 0x7fdbe8020230}, unwinds = {next = 0x7fdbe8020240, prev = 0x7fdbe8020240}, wip = { next = 0x7fdbe8020250, prev = 0x7fdbe8020250}, stub = 0x7fdbe8062c3c, write_size = 131072, orig_size = 4096, total_size = 0, op_ret = -1, op_errno = 116, refcount = 1, wb_inode = 0x7fdbe803a5f0, fop = GF_FOP_WRITE, lk_owner = {len = 8, data = '\000' }, iobref = 0x7fdbe80311a0, gen = 4, fd = 0x7fdbe805c89c, wind_count = 3, ordering = {size = 131072, off = 1220608, append = 0, tempted = -1, lied = -1, fulfilled = 0, go = 0}} (gdb) print *((wb_request_t *)0x7fdbe8068c30) $4 = {all = {next = 0x7fdbe8021cd0, prev = 0x7fdbe8020200}, todo = {next = 0x7fdbe8021ce0, prev = 0x7fdbe8020210}, lie = {next = 0x7fdbe803a628, prev = 0x7fdbe8020220}, winds = {next = 0x7fdbe8068c60, prev = 0x7fdbe8068c60}, unwinds = {next = 0x7fdbe8068c70, prev = 0x7fdbe8068c70}, wip = { next = 0x7fdbe8068c80, prev = 0x7fdbe8068c80}, stub = 0x7fdbe806746c, write_size = 118784, orig_size = 4096, total_size = 0, op_ret = -1, op_errno = 116, refcount = 1, wb_inode = 0x7fdbe803a5f0, fop = GF_FOP_WRITE, lk_owner = {len = 8, data = '\000' }, iobref = 0x7fdbe8052b10, gen = 5, fd = 0x7fdbe805c89c, wind_count = 2, ordering = {size = 118784, off = 1351680, append = 0, tempted = -1, lied = -1, fulfilled = 0, go = 0}} you can see they are all on 'todo' queue, and FLUSH op fd is not the same WRITE op fd. > Change-Id: Id687f9cd3b9f281e1a97c83f1ce981ede272b8ab > BUG: 1372211 > Signed-off-by: Ryan Ding Change-Id: Id687f9cd3b9f281e1a97c83f1ce981ede272b8ab BUG: 1390840 Signed-off-by: Ryan Ding Reviewed-on: http://review.gluster.org/15763 Tested-by: Raghavendra G Reviewed-by: Raghavendra G Smoke: Gluster Build System NetBSD-regression: NetBSD Build System CentOS-regression: Gluster Build System --- xlators/performance/write-behind/src/write-behind.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'xlators') diff --git a/xlators/performance/write-behind/src/write-behind.c b/xlators/performance/write-behind/src/write-behind.c index 4ee10b5249d..76ecd7cb6fe 100644 --- a/xlators/performance/write-behind/src/write-behind.c +++ b/xlators/performance/write-behind/src/write-behind.c @@ -285,6 +285,10 @@ wb_requests_conflict (wb_request_t *lie, wb_request_t *req) us in the todo list */ return _gf_false; + /* requests from different fd do not conflict with each other. */ + if (req->fd && (req->fd != lie->fd)) + return _gf_false; + if (lie->ordering.append) /* all modifications wait for the completion of outstanding append */ -- cgit