From 6bbce9b1a48d5d50a2044b4518270e952331f159 Mon Sep 17 00:00:00 2001 From: Pranith Kumar K Date: Tue, 8 Sep 2015 16:23:36 +0530 Subject: cluster/ec: Implement gfid-hash read-policy Add a policy in ec to performs reads from same bricks as long as they are good. Based on the gfid of the file/directory it determines the bricks to be considered for reading. >Change-Id: Ic97b5c54c086a28b5e07a330a4fd448551b49376 >BUG: 1261260 >Signed-off-by: Pranith Kumar K >Reviewed-on: http://review.gluster.org/12133 >Tested-by: NetBSD Build System >Tested-by: Gluster Build System >Reviewed-by: Xavier Hernandez BUG: 1270705 Change-Id: Ibf0d21d7210125fa7aaa12b3f98bcdf7cd89ef02 Signed-off-by: Pranith Kumar K Reviewed-on: http://review.gluster.org/12456 Tested-by: NetBSD Build System Tested-by: Gluster Build System --- xlators/cluster/ec/src/ec.c | 39 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 38 insertions(+), 1 deletion(-) (limited to 'xlators/cluster/ec/src/ec.c') diff --git a/xlators/cluster/ec/src/ec.c b/xlators/cluster/ec/src/ec.c index 7abd5cf8fa7..f139482c705 100644 --- a/xlators/cluster/ec/src/ec.c +++ b/xlators/cluster/ec/src/ec.c @@ -21,6 +21,11 @@ #include "ec-messages.h" #include "ec-heald.h" +static char *ec_read_policies[EC_READ_POLICY_MAX + 1] = { + [EC_ROUND_ROBIN] = "round-robin", + [EC_GFID_HASH] = "gfid-hash", + [EC_READ_POLICY_MAX] = NULL +}; #define EC_MAX_FRAGMENTS EC_METHOD_MAX_FRAGMENTS /* The maximum number of nodes is derived from the maximum allowed fragments * using the rule that redundancy cannot be equal or greater than the number @@ -231,10 +236,24 @@ ec_configure_background_heal_opts (ec_t *ec, int background_heals, ec->background_heals = background_heals; } +int +ec_assign_read_policy (ec_t *ec, char *read_policy) +{ + int read_policy_idx = -1; + + read_policy_idx = gf_get_index_by_elem (ec_read_policies, read_policy); + if (read_policy_idx < 0 || read_policy_idx >= EC_READ_POLICY_MAX) + return -1; + + ec->read_policy = read_policy_idx; + return 0; +} + int32_t reconfigure (xlator_t *this, dict_t *options) { ec_t *ec = this->private; + char *read_policy = NULL; uint32_t heal_wait_qlen = 0; uint32_t background_heals = 0; @@ -248,6 +267,10 @@ reconfigure (xlator_t *this, dict_t *options) uint32, failed); ec_configure_background_heal_opts (ec, background_heals, heal_wait_qlen); + GF_OPTION_RECONF ("read-policy", read_policy, options, str, failed); + if (ec_assign_read_policy (ec, read_policy)) + goto failed; + return 0; failed: return -1; @@ -512,7 +535,8 @@ notify (xlator_t *this, int32_t event, void *data, ...) int32_t init (xlator_t *this) { - ec_t *ec = NULL; + ec_t *ec = NULL; + char *read_policy = NULL; if (this->parents == NULL) { @@ -574,6 +598,9 @@ init (xlator_t *this) GF_OPTION_INIT ("heal-wait-qlength", ec->heal_wait_qlen, uint32, failed); ec_configure_background_heal_opts (ec, ec->background_heals, ec->heal_wait_qlen); + GF_OPTION_INIT ("read-policy", read_policy, str, failed); + if (ec_assign_read_policy (ec, read_policy)) + goto failed; if (ec->shd.iamshd) ec_selfheal_daemon_init (this); @@ -1189,6 +1216,7 @@ int32_t ec_dump_private(xlator_t *this) gf_proc_dump_write("heal-wait-qlength", "%d", ec->heal_wait_qlen); gf_proc_dump_write("healers", "%d", ec->healers); gf_proc_dump_write("heal-waiters", "%d", ec->heal_waiters); + gf_proc_dump_write("read-policy", "%s", ec_read_policies[ec->read_policy]); return 0; } @@ -1288,5 +1316,14 @@ struct volume_options options[] = .description = "This option can be used to control number of heals" " that can wait", }, + { .key = {"read-policy" }, + .type = GF_OPTION_TYPE_STR, + .value = {"round-robin", "gfid-hash"}, + .default_value = "round-robin", + .description = "inode-read fops happen only on 'k' number of bricks in" + " n=k+m disperse subvolume. 'round-robin' selects the read" + " subvolume using round-robin algo. 'gfid-hash' selects read" + " subvolume based on hash of the gfid of that file/directory.", + }, { } }; -- cgit