Note: This bug is displayed in read-only format because
the product is no longer active in Red Hat Bugzilla.
RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Description of problem:
Lock contention on the connection mutex between listening thread handling the network events and the worker threads handling the ldap operations sometime impacts the global server performance.
How reproducible:
Setup an instance (named standalone1) and having suffix dc=example,dc=com with default tests entries generated by dscreate"
Run: dsconf standalone1 config replace nsslapd-accesslog-level=4
(To turn off the log of standard operations and turn on the log of internal operations)
Run: ldclt -p 389 -e esearch -b "dc=example,dc=com" -f "cn=demo"
In another windows run a loop on:
ldapsearch -Q -LLL -Y EXTERNAL -H ldapi://%2fvar%2frun%2fslapd-standalone1.socket -b dc=example,dc=com cn=demo
Actual results:
Then you should see the ldclt performance dropping significantly:
ldclt[416127]: Average rate: 14371.20/thr (14371.20/sec), total: 143712
ldclt[416127]: Average rate: 14527.00/thr (14527.00/sec), total: 145270
ldclt[416127]: Average rate: 8274.10/thr (8274.10/sec), total: 82741
ldclt[416127]: Average rate: 4551.20/thr (4551.20/sec), total: 45512
ldclt[416127]: Average rate: 4191.30/thr (4191.30/sec), total: 41913
Expected results:
Should not have a significant performance drop.
Additional info:
Problem is very similar to the BZ 2224505 issue but when doing a
SASL bind with EXTERNAL method instead of a paged result search and was first detected during code review when looking for other piece of code that may have the same contention issue. But the impact is much less serious: usually not perceptible with standard default configuration. (I needed to slow the internal operations (by enabling the log of these operation) to see clearly the performance impact.
Comment 1RHEL Program Management
2023-09-19 14:23:19 UTC
Issue migration from Bugzilla to Jira is in process at this time. This will be the last message in Jira copied from the Bugzilla bug.
Comment 2RHEL Program Management
2023-09-19 14:23:56 UTC
This BZ has been automatically migrated to the issues.redhat.com Red Hat Issue Tracker. All future work related to this report will be managed there.
Due to differences in account names between systems, some fields were not replicated. Be sure to add yourself to Jira issue's "Watchers" field to continue receiving updates and add others to the "Need Info From" field to continue requesting information.
To find the migrated issue, look in the "Links" section for a direct link to the new issue location. The issue key will have an icon of 2 footprints next to it, and begin with "RHEL-" followed by an integer. You can also find this issue by visiting https://issues.redhat.com/issues/?jql= and searching the "Bugzilla Bug" field for this BZ's number, e.g. a search like:
"Bugzilla Bug" = 1234567
In the event you have trouble locating or viewing this issue, you can file an issue by sending mail to rh-issues. You can also visit https://access.redhat.com/articles/7032570 for general account information.