From 8a0d85eb936f9483a5d23d67cf5989351d5f86d7 Mon Sep 17 00:00:00 2001 From: Raghavendra G Date: Tue, 22 Sep 2009 01:38:12 +0000 Subject: performance/write-behind: Aggregate adjacent contiguous write-buffers into single iobuf. Signed-off-by: Anand V. Avati BUG: 276 (write behind needs to be optimized.) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=276 --- .../performance/write-behind/src/write-behind.c | 78 +++++++++++++++++++++- 1 file changed, 77 insertions(+), 1 deletion(-) (limited to 'xlators/performance/write-behind') diff --git a/xlators/performance/write-behind/src/write-behind.c b/xlators/performance/write-behind/src/write-behind.c index d5eefed23..b38f1665b 100644 --- a/xlators/performance/write-behind/src/write-behind.c +++ b/xlators/performance/write-behind/src/write-behind.c @@ -53,6 +53,7 @@ typedef struct wb_file { int32_t op_ret; int32_t op_errno; list_head_t request; + list_head_t passive_requests; fd_t *fd; gf_lock_t lock; xlator_t *this; @@ -262,6 +263,7 @@ wb_file_create (xlator_t *this, fd_t *fd) } INIT_LIST_HEAD (&file->request); + INIT_LIST_HEAD (&file->passive_requests); /* fd_ref() not required, file should never decide the existance of @@ -1596,6 +1598,70 @@ out: } +/* this procedure assumes that write requests have only one vector to write */ +void +__wb_collapse_write_bufs (list_head_t *requests, size_t page_size) +{ + + off_t offset_expected = 0; + size_t space_left = 0, length = 0, *iov_len = NULL; + char *ptr = NULL, first_request = 1; + wb_request_t *request = NULL, *tmp = NULL; + + list_for_each_entry_safe (request, tmp, requests, list) { + if ((request->stub->fop != GF_FOP_WRITE) + || (request->flags.write_request.stack_wound)) { + space_left = 0; + ptr = NULL; + first_request = 1; + continue; + } + + if (request->flags.write_request.write_behind) { + length = iov_length (request->stub->args.writev.vector, + request->stub->args.writev.count); + + if (first_request) { + first_request = 0; + offset_expected = request->stub->args.writev.off; + } + + if (request->stub->args.writev.off != offset_expected) { + offset_expected = request->stub->args.writev.off + length; + space_left = page_size - length; + ptr = request->stub->args.writev.vector[0].iov_base + + length; + iov_len = &request->stub->args.writev.vector[0].iov_len; + continue; + } + + if (space_left >= length) { + iov_unload (ptr, + request->stub->args.writev.vector, + request->stub->args.writev.count); + space_left -= length; + ptr += length; + *iov_len = *iov_len + length; + + list_move_tail (&request->list, + &request->file->passive_requests); + + __wb_request_unref (request); + } else { + space_left = page_size - length; + ptr = request->stub->args.writev.vector[0].iov_base + + length; + iov_len = &request->stub->args.writev.vector[0].iov_len; + } + } else { + break; + } + + offset_expected += length; + } +} + + int32_t wb_process_queue (call_frame_t *frame, wb_file_t *file, char flush_all) { @@ -1617,6 +1683,17 @@ wb_process_queue (call_frame_t *frame, wb_file_t *file, char flush_all) size = conf->aggregate_size; LOCK (&file->lock); { + /* + * make sure requests are marked for unwinding and adjacent + * continguous write buffers (each of size less than that of + * an iobuf) are packed properly so that iobufs are filled to + * their maximum capacity, before calling __wb_mark_winds. + */ + __wb_mark_unwinds (&file->request, &unwinds, conf->window_size); + + __wb_collapse_write_bufs (&file->request, + file->this->ctx->page_size); + count = __wb_get_other_requests (&file->request, &other_requests); @@ -1625,7 +1702,6 @@ wb_process_queue (call_frame_t *frame, wb_file_t *file, char flush_all) flush_all); } - __wb_mark_unwinds (&file->request, &unwinds, conf->window_size); } UNLOCK (&file->lock); -- cgit