From: Andrew Perepechko Date: Tue, 29 May 2018 14:21:44 +0000 (-0400) Subject: staging: lustre: mdc: excessive memory consumption by the xattr cache X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=889cea43c54b91b92011649ce53db4fdc51ed86c;p=linux.git staging: lustre: mdc: excessive memory consumption by the xattr cache The refill operation of the xattr cache does not know the reply size in advance, so it makes a guess based on the maxeasize value returned by the MDS. In practice, it allocates 16 KiB for the common case and 4 MiB for the large xattr case. However, a typical reply is just a few hundred bytes. If we follow the conservative approach, we can prepare a single memory page for the reply. It is large enough for any reasonable xattr set and, at the same time, it does not require multiple page memory reclaim, which can be costly. If, for a specific file, the reply is larger than a single page, the client is prepared to handle that and will fall back to non-cached xattr code. Indeed, if this happens often and xattrs are often used to store large values, it makes sense to disable the xattr cache at all since it wasn't designed for such [mis]use. Signed-off-by: Andrew Perepechko Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-9417 Reviewed-on: https://review.whamcloud.com/26887 Reviewed-by: Fan Yong Reviewed-by: Ben Evans Reviewed-by: Oleg Drokin Signed-off-by: James Simmons Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/lustre/lustre/mdc/mdc_locks.c b/drivers/staging/lustre/lustre/mdc/mdc_locks.c index 65a5341e8a7c4..a8aa0fa5e87ac 100644 --- a/drivers/staging/lustre/lustre/mdc/mdc_locks.c +++ b/drivers/staging/lustre/lustre/mdc/mdc_locks.c @@ -315,6 +315,10 @@ mdc_intent_open_pack(struct obd_export *exp, struct lookup_intent *it, return req; } +#define GA_DEFAULT_EA_NAME_LEN 20 +#define GA_DEFAULT_EA_VAL_LEN 250 +#define GA_DEFAULT_EA_NUM 10 + static struct ptlrpc_request * mdc_intent_getxattr_pack(struct obd_export *exp, struct lookup_intent *it, @@ -323,7 +327,6 @@ mdc_intent_getxattr_pack(struct obd_export *exp, struct ptlrpc_request *req; struct ldlm_intent *lit; int rc, count = 0; - u32 maxdata; LIST_HEAD(cancels); req = ptlrpc_request_alloc(class_exp2cliimp(exp), @@ -341,20 +344,20 @@ mdc_intent_getxattr_pack(struct obd_export *exp, lit = req_capsule_client_get(&req->rq_pill, &RMF_LDLM_INTENT); lit->opc = IT_GETXATTR; - maxdata = class_exp2cliimp(exp)->imp_connect_data.ocd_max_easize; - /* pack the intended request */ - mdc_pack_body(req, &op_data->op_fid1, op_data->op_valid, maxdata, -1, - 0); + mdc_pack_body(req, &op_data->op_fid1, op_data->op_valid, + GA_DEFAULT_EA_NAME_LEN * GA_DEFAULT_EA_NUM, -1, 0); - req_capsule_set_size(&req->rq_pill, &RMF_EADATA, RCL_SERVER, maxdata); + req_capsule_set_size(&req->rq_pill, &RMF_EADATA, RCL_SERVER, + GA_DEFAULT_EA_NAME_LEN * GA_DEFAULT_EA_NUM); - req_capsule_set_size(&req->rq_pill, &RMF_EAVALS, RCL_SERVER, maxdata); + req_capsule_set_size(&req->rq_pill, &RMF_EAVALS, RCL_SERVER, + GA_DEFAULT_EA_NAME_LEN * GA_DEFAULT_EA_NUM); - req_capsule_set_size(&req->rq_pill, &RMF_EAVALS_LENS, - RCL_SERVER, maxdata); + req_capsule_set_size(&req->rq_pill, &RMF_EAVALS_LENS, RCL_SERVER, + sizeof(u32) * GA_DEFAULT_EA_NUM); - req_capsule_set_size(&req->rq_pill, &RMF_ACL, RCL_SERVER, maxdata); + req_capsule_set_size(&req->rq_pill, &RMF_ACL, RCL_SERVER, 0); ptlrpc_request_set_replen(req);