From f2f3d74c835b68ad9ec63ec112870829a823a1fb Mon Sep 17 00:00:00 2001 From: Mohammed Rafi KC Date: Thu, 6 Jul 2017 13:26:42 +0530 Subject: mgtm/core : use sha hash function for volfile check We are storing the entire volfile and using this to check volfile change. With brick multiplexing there will be lot of graphs per process which will increase the memory foot print of the process. So instead of storing the entire graph we could use sha256 and we can compare the hash to see whether volfile change happened or not. Also with Brick multiplexing, the direct comparison of vol file is not correct. There are two problems. Problem 1: We are currently storing one single graph (the last updated volfile) whereas, what we need is the entire graph with all atttached bricks. If we fix this issue, we have second problem Problem 2: With multiplexing we have a graph that contains multiple bricks. But what we are checking as part of the reconfigure is, comparing the entire graph with one single graph, which will always fail. Solution: We create list in glusterfs_ctx_t that stores sha256 hash of individual brick graphs. When a graph changes happens we compare the stored hash and the current hash. If the hash matches, then no need for reconfigure. Otherwise we first do the reconfigure and then update the hash. For now, gfapi has not changed this way. Meaning when gfapi volfile fetch or reconfigure happens, we still store the entire graph and compare, each memory. This is fine, because libgfapi will not load brick graphs. But changing the libgfapi will make the code similar in both glusterfsd-mgmt and api. Also it helps to reduce some memory. Change-Id: I9df917a771a52b95622ab8f63af34ec390163a77 BUG: 1467986 Signed-off-by: Mohammed Rafi KC Reviewed-on: https://review.gluster.org/17709 Smoke: Gluster Build System Reviewed-by: Pranith Kumar Karampuri CentOS-regression: Gluster Build System Reviewed-by: Atin Mukherjee Reviewed-by: Amar Tumballi --- glusterfsd/src/glusterfsd-mgmt.c | 98 +++++++++++++++++++++++++++------------- 1 file changed, 66 insertions(+), 32 deletions(-) (limited to 'glusterfsd') diff --git a/glusterfsd/src/glusterfsd-mgmt.c b/glusterfsd/src/glusterfsd-mgmt.c index c17bf3bb6fc..ca706d1020d 100644 --- a/glusterfsd/src/glusterfsd-mgmt.c +++ b/glusterfsd/src/glusterfsd-mgmt.c @@ -1761,12 +1761,6 @@ out: return ret; } - -/* XXX: move these into @ctx */ -static char *oldvolfile = NULL; -static int oldvollen; - - int mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count, void *myframe) @@ -1777,7 +1771,10 @@ mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count, int ret = 0, locked = 0; ssize_t size = 0; FILE *tmpfp = NULL; - char *volfilebuf = NULL; + char *volfile_id = NULL; + gf_volfile_t *volfile_obj = NULL; + gf_volfile_t *volfile_tmp = NULL; + char sha256_hash[SHA256_DIGEST_LENGTH] = {0, }; frame = myframe; ctx = frame->this->ctx; @@ -1804,14 +1801,29 @@ mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count, ret = 0; size = rsp.op_ret; + glusterfs_compute_sha256 ((const unsigned char *) rsp.spec, size, + sha256_hash); + + volfile_id = frame->local; + LOCK (&ctx->volfile_lock); { locked = 1; - if (size == oldvollen && (memcmp (oldvolfile, rsp.spec, size) == 0)) { - gf_log (frame->this->name, GF_LOG_INFO, - "No change in volfile, continuing"); - goto out; + list_for_each_entry (volfile_obj, &ctx->volfile_list, + volfile_list) { + if (!strcmp (volfile_id, volfile_obj->vol_id)) { + if (!strncmp (sha256_hash, + volfile_obj->volfile_checksum, + sizeof (volfile_obj->volfile_checksum))) { + gf_log (frame->this->name, GF_LOG_INFO, + "No change in volfile," + "continuing"); + goto out; + } + volfile_tmp = volfile_obj; + break; + } } tmpfp = tmpfile (); @@ -1835,21 +1847,19 @@ mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count, * return -1(or -ve) =======> Some Internal Error occurred during the operation */ - ret = glusterfs_volfile_reconfigure (oldvollen, tmpfp, ctx, oldvolfile); + ret = glusterfs_volfile_reconfigure (tmpfp, ctx); if (ret == 0) { gf_log ("glusterfsd-mgmt", GF_LOG_DEBUG, "No need to re-load volfile, reconfigure done"); - if (oldvolfile) - volfilebuf = GF_REALLOC (oldvolfile, size); - else - volfilebuf = GF_CALLOC (1, size, gf_common_mt_char); - if (!volfilebuf) { + if (!volfile_tmp) { ret = -1; + gf_log ("mgmt", GF_LOG_ERROR, "Graph " + "reconfigure succeeded with out having " + "checksum."); goto out; } - oldvolfile = volfilebuf; - oldvollen = size; - memcpy (oldvolfile, rsp.spec, size); + strncpy (volfile_tmp->volfile_checksum, sha256_hash, + sizeof (volfile_tmp->volfile_checksum)); goto out; } @@ -1865,19 +1875,23 @@ mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count, if (ret) goto out; - if (oldvolfile) - volfilebuf = GF_REALLOC (oldvolfile, size); - else - volfilebuf = GF_CALLOC (1, size, gf_common_mt_char); + if (!volfile_tmp) { + volfile_tmp = GF_CALLOC (1, sizeof (gf_volfile_t), + gf_common_volfile_t); + if (!volfile_tmp) { + ret = -1; + goto out; + } - if (!volfilebuf) { - ret = -1; - goto out; + INIT_LIST_HEAD (&volfile_tmp->volfile_list); + list_add (&volfile_tmp->volfile_list, + &ctx->volfile_list); + snprintf (volfile_tmp->vol_id, + sizeof (volfile_tmp->vol_id), "%s", + volfile_id); } - - oldvolfile = volfilebuf; - oldvollen = size; - memcpy (oldvolfile, rsp.spec, size); + strncpy (volfile_tmp->volfile_checksum, sha256_hash, + sizeof (volfile_tmp->volfile_checksum)); } UNLOCK (&ctx->volfile_lock); @@ -1894,7 +1908,11 @@ out: if (locked) UNLOCK (&ctx->volfile_lock); - STACK_DESTROY (frame->root); + if (frame) { + GF_FREE (frame->local); + frame->local = NULL; + STACK_DESTROY (frame->root); + } free (rsp.spec); @@ -1941,6 +1959,15 @@ glusterfs_volfile_fetch_one (glusterfs_ctx_t *ctx, char *volfile_id) req.key = volfile_id; req.flags = 0; + /* + * We are only storing one variable in local, hence using the same + * variable. If multiple local variable is required, create a struct. + */ + frame->local = gf_strdup (volfile_id); + if (!frame->local) { + ret = -1; + goto out; + } dict = dict_new (); if (!dict) { @@ -1990,6 +2017,13 @@ out: GF_FREE (req.xdata.xdata_val); if (dict) dict_unref (dict); + if (ret && frame) { + /* Free the frame->local fast, because we have not used memget + */ + GF_FREE (frame->local); + frame->local = NULL; + STACK_DESTROY (frame->root); + } return ret; } -- cgit