From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Simmons Date: Thu, 27 Feb 2020 16:14:24 -0500 Subject: [lustre-devel] [PATCH 396/622] lnet: libcfs: Reduce memory frag due to HA debug msg In-Reply-To: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> References: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> Message-ID: <1582838290-17243-397-git-send-email-jsimmons@infradead.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org From: Ann Koehler The dynamic allocation and freeing of Lustre trace pages has been shown to cause memory fragmentation that sometimes prevents applications from getting the contiguous memory they need to run. In one such occurrence over 99% of the messages were the matched open trace messages issued by mdc_close(): DEBUG_REQ(D_HA, mod->mod_open_req, "matched open; tag %d", tag); D_HA is included in the default set of debug flags. This has proven to be quite useful in debugging connection issues particularly at mount time. So removing all HA message from the default tracing is not a good option. However, the matched open debug message has not proven itself to be as generally useful. So moving the message under a different debug flag, one that must be explicitly enabled, reduces the amount of default tracing and thereby helps reduce fragmentation without causing much loss of functionality. Using D_RPCTRACE to match the corresponding open debug message in mdc_set_open_replay_data. Cray-bug-id: LUS-7560 WC-bug-id: https://jira.whamcloud.com/browse/LU-12524 Lustre-commit: 076a5961f20b ("LU-12524 libcfs: Reduce memory frag due to HA debug msg") Signed-off-by: Ann Koehler Reviewed-on: https://review.whamcloud.com/35449 Reviewed-by: James Simmons Reviewed-by: Andreas Dilger Signed-off-by: James Simmons --- fs/lustre/mdc/mdc_request.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/lustre/mdc/mdc_request.c b/fs/lustre/mdc/mdc_request.c index a26efa1..7bc6196 100644 --- a/fs/lustre/mdc/mdc_request.c +++ b/fs/lustre/mdc/mdc_request.c @@ -937,7 +937,7 @@ static int mdc_close(struct obd_export *exp, struct md_op_data *op_data, mod->mod_close_req = req; - DEBUG_REQ(D_HA, mod->mod_open_req, "matched open"); + DEBUG_REQ(D_RPCTRACE, mod->mod_open_req, "matched open"); /* We no longer want to preserve this open for replay even * though the open was committed. b=3632, b=3633 */ -- 1.8.3.1