From 641b3a9164227db52df1aab05795c90d06b315f2 Mon Sep 17 00:00:00 2001 From: Ravishankar N Date: Wed, 21 Oct 2015 21:05:46 +0530 Subject: afr: write zeros to sink for non-sparse files Problem: If a file is created with zeroes ('dd', 'fallocate' etc.) when a brick is down, the self-heal does not write the zeroes to the sink after it comes up. Consequenty, there is a mismatch in disk-usage amongst the bricks of the replica. Fix: If we definitely know that the file is not sparse, then write the zeroes to the sink even if the checksums match. Change-Id: Ic739b3da5dbf47d99801c0e1743bb13aeb3af864 BUG: 1272460 Signed-off-by: Ravishankar N Reviewed-on: http://review.gluster.org/12371 Reviewed-by: Pranith Kumar Karampuri Tested-by: Gluster Build System --- xlators/cluster/afr/src/afr-self-heal-data.c | 57 ++++++++++++++++++++-------- 1 file changed, 41 insertions(+), 16 deletions(-) (limited to 'xlators/cluster/afr/src/afr-self-heal-data.c') diff --git a/xlators/cluster/afr/src/afr-self-heal-data.c b/xlators/cluster/afr/src/afr-self-heal-data.c index 36d658fa454..4529462c3a9 100644 --- a/xlators/cluster/afr/src/afr-self-heal-data.c +++ b/xlators/cluster/afr/src/afr-self-heal-data.c @@ -28,13 +28,18 @@ __checksum_cbk (call_frame_t *frame, void *cookie, xlator_t *this, dict_t *xdata) { afr_local_t *local = NULL; + struct afr_reply *replies = NULL; int i = (long) cookie; local = frame->local; - - local->replies[i].valid = 1; - local->replies[i].op_ret = op_ret; - local->replies[i].op_errno = op_errno; + replies = local->replies; + + replies[i].valid = 1; + replies[i].op_ret = op_ret; + replies[i].op_errno = op_errno; + if (xdata) + replies[i].buf_has_zeroes = dict_get_str_boolean (xdata, + "buf-has-zeroes", _gf_false); if (strong) memcpy (local->replies[i].checksum, strong, MD5_DIGEST_LENGTH); @@ -70,19 +75,23 @@ attr_cbk (call_frame_t *frame, void *cookie, xlator_t *this, static gf_boolean_t -__afr_selfheal_data_checksums_match (call_frame_t *frame, xlator_t *this, - fd_t *fd, int source, - unsigned char *healed_sinks, - off_t offset, size_t size) +__afr_can_skip_data_block_heal (call_frame_t *frame, xlator_t *this, fd_t *fd, + int source, unsigned char *healed_sinks, + off_t offset, size_t size, + struct iatt *poststat) { afr_private_t *priv = NULL; afr_local_t *local = NULL; unsigned char *wind_subvols = NULL; + gf_boolean_t checksum_match = _gf_true; + dict_t *xdata = NULL; int i = 0; priv = this->private; local = frame->local; - + xdata = dict_new(); + if (xdata) + i = dict_set_int32 (xdata, "check-zero-filled", 1); wind_subvols = alloca0 (priv->child_count); for (i = 0; i < priv->child_count; i++) { if (i == source || healed_sinks[i]) @@ -90,7 +99,9 @@ __afr_selfheal_data_checksums_match (call_frame_t *frame, xlator_t *this, } AFR_ONLIST (wind_subvols, frame, __checksum_cbk, rchecksum, fd, - offset, size, NULL); + offset, size, xdata); + if (xdata) + dict_unref (xdata); if (!local->replies[source].valid || local->replies[source].op_ret != 0) return _gf_false; @@ -101,12 +112,26 @@ __afr_selfheal_data_checksums_match (call_frame_t *frame, xlator_t *this, if (local->replies[i].valid) { if (memcmp (local->replies[source].checksum, local->replies[i].checksum, - MD5_DIGEST_LENGTH)) - return _gf_false; + MD5_DIGEST_LENGTH)) { + checksum_match = _gf_false; + break; + } } } - return _gf_true; + if (checksum_match) { + if (HAS_HOLES (poststat)) + return _gf_true; + + /* For non-sparse files, we might be better off writing the + * zeroes to sinks to avoid mismatch of disk-usage in bricks. */ + if (local->replies[source].buf_has_zeroes) + return _gf_false; + else + return _gf_true; + } + + return _gf_false; } @@ -220,7 +245,6 @@ __afr_selfheal_data_read_write (call_frame_t *frame, xlator_t *this, fd_t *fd, return ret; } - static int afr_selfheal_data_block (call_frame_t *frame, xlator_t *this, fd_t *fd, int source, unsigned char *healed_sinks, off_t offset, @@ -244,8 +268,9 @@ afr_selfheal_data_block (call_frame_t *frame, xlator_t *this, fd_t *fd, } if (type == AFR_SELFHEAL_DATA_DIFF && - __afr_selfheal_data_checksums_match (frame, this, fd, source, - healed_sinks, offset, size)) { + __afr_can_skip_data_block_heal (frame, this, fd, source, + healed_sinks, offset, size, + &replies[source].poststat)) { ret = 0; goto unlock; } -- cgit