<!-- 
RSS generated by JIRA (9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66) at Thu Feb 08 05:18:40 UTC 2024

It is possible to restrict the fields that are returned in this document by specifying the 'field' parameter in your request.
For example, to request only the issue key and summary append 'field=key&field=summary' to the URL of your request.
-->
<rss version="0.92" >
<channel>
    <title>MongoDB Jira</title>
    <link>https://jira.mongodb.org</link>
    <description>This file is an XML representation of an issue</description>
    <language>en-us</language>    <build-info>
        <version>9.7.1</version>
        <build-number>970001</build-number>
        <build-date>13-04-2023</build-date>
    </build-info>


<item>
            <title>[SERVER-49005] Improve concurrency testing for mongos cluster cursor manager</title>
                <link>https://jira.mongodb.org/browse/SERVER-49005</link>
                <project id="10000" key="SERVER">Core Server</project>
                    <description>&lt;p&gt;&lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-27796&quot; title=&quot;Invariant failure in cluster_cursor_manager.cpp, numDeleted == 1&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-27796&quot;&gt;&lt;del&gt;SERVER-27796&lt;/del&gt;&lt;/a&gt; (still unsolved) indicates that there may be a bug related to concurrency control in the cluster cursor manager. While we have a&#160;&lt;a href=&quot;https://github.com/mongodb/mongo/blob/c331ba2fad9d9867227cbc20c5ab79143cff29e2/jstests/concurrency/fsm_workloads/invalidated_cursors.js#L16&quot; class=&quot;external-link&quot; target=&quot;_blank&quot; rel=&quot;nofollow noopener&quot;&gt;JS concurrency test&lt;/a&gt;&#160;(also &lt;a href=&quot;https://github.com/mongodb/mongo/blob/master/jstests/concurrency/fsm_workloads/kill_multicollection_aggregation.js&quot; class=&quot;external-link&quot; target=&quot;_blank&quot; rel=&quot;nofollow noopener&quot;&gt;this one&lt;/a&gt;) which target mongos cursor manager, the bug has never been reproduced in our own test environment.&lt;/p&gt;

&lt;p&gt;&#160;&lt;/p&gt;

&lt;p&gt;We should consider adding a unit test which stresses the concurrency control of the cluster cursor manager directly, in similar spirit to d_concurrency_test, which directly&#160;&lt;a href=&quot;https://github.com/mongodb/mongo/blob/2e8fd8b72f95af8662bd26c18057f4b8d94e6300/src/mongo/db/concurrency/d_concurrency_test.cpp#L1267&quot; class=&quot;external-link&quot; target=&quot;_blank&quot; rel=&quot;nofollow noopener&quot;&gt;stresses&lt;/a&gt;&#160;the mongod locking code with 32 threads. If the cause of &lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-27796&quot; title=&quot;Invariant failure in cluster_cursor_manager.cpp, numDeleted == 1&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-27796&quot;&gt;&lt;del&gt;SERVER-27796&lt;/del&gt;&lt;/a&gt; is a concurrency control issue in the CCC, this would give us a better chance of reproducing it.&lt;/p&gt;

&lt;p&gt;The existing JS test also runs with a mere &lt;a href=&quot;https://github.com/mongodb/mongo/blob/c331ba2fad9d9867227cbc20c5ab79143cff29e2/jstests/concurrency/fsm_workloads/invalidated_cursors.js#L25&quot; class=&quot;external-link&quot; target=&quot;_blank&quot; rel=&quot;nofollow noopener&quot;&gt;3 collections&lt;/a&gt;. The mongos code which triggers the invariant failure has to do with all cursors for a collection being destroyed, meaning that the JS test likely does not exercise this path very often. We should investigate whether this is indeed the case, and allow the test to run with more collections (assuming it won&apos;t make the existing workload useless) if so.&lt;/p&gt;</description>
                <environment></environment>
        <key id="1385915">SERVER-49005</key>
            <summary>Improve concurrency testing for mongos cluster cursor manager</summary>
                <type id="4" iconUrl="https://jira.mongodb.org/secure/viewavatar?size=xsmall&amp;avatarId=14710&amp;avatarType=issuetype">Improvement</type>
                                            <priority id="3" iconUrl="https://jira.mongodb.org/images/icons/priorities/major.svg">Major - P3</priority>
                        <status id="10038" iconUrl="https://jira.mongodb.org/images/icons/subtask.gif" description="">Backlog</status>
                    <statusCategory id="2" key="new" colorName="default"/>
                                    <resolution id="-1">Unresolved</resolution>
                                        <assignee username="backlog-query-execution">Backlog - Query Execution</assignee>
                                    <reporter username="ian.boros@mongodb.com">Ian Boros</reporter>
                        <labels>
                            <label>qexec-team</label>
                    </labels>
                <created>Mon, 22 Jun 2020 16:14:18 +0000</created>
                <updated>Tue, 6 Dec 2022 02:21:30 +0000</updated>
                                                                            <component>Querying</component>
                                        <votes>0</votes>
                                    <watches>2</watches>
                                                                                                                    <issuelinks>
                            <issuelinktype id="10012">
                    <name>Related</name>
                                            <outwardlinks description="related to">
                                        <issuelink>
            <issuekey id="348412">SERVER-27796</issuekey>
        </issuelink>
                            </outwardlinks>
                                                        </issuelinktype>
                    </issuelinks>
                <attachments>
                    </attachments>
                <subtasks>
                    </subtasks>
                <customfields>
                                                <customfield id="customfield_10050" key="com.atlassian.jira.toolkit:comments">
                        <customfieldname># Replies</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>0.0</customfieldvalue>
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                <customfield id="customfield_12751" key="com.atlassian.jira.plugin.system.customfieldtypes:multiselect">
                        <customfieldname>Assigned Teams</customfieldname>
                        <customfieldvalues>
                                <customfieldvalue key="25125"><![CDATA[Query Execution]]></customfieldvalue>
    
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                <customfield id="customfield_10052" key="com.atlassian.jira.toolkit:dayslastcommented">
                        <customfieldname>Days since reply</customfieldname>
                        <customfieldvalues>
                                        3 years, 33 weeks, 2 days ago
    
                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_18254" key="com.onresolve.jira.groovy.groovyrunner:scripted-field">
                        <customfieldname>Dependencies</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue><![CDATA[]]></customfieldvalue>


                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_15850" key="com.atlassian.jira.plugins.jira-development-integration-plugin:devsummary">
                        <customfieldname>Development</customfieldname>
                        <customfieldvalues>
                            
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        <customfield id="customfield_10057" key="com.atlassian.jira.toolkit:lastusercommented">
                        <customfieldname>Last comment by Customer</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>true</customfieldvalue>
                        </customfieldvalues>
                    </customfield>
                                                                                            <customfield id="customfield_10056" key="com.atlassian.jira.toolkit:lastupdaterorcommenter">
                        <customfieldname>Last commenter</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>alexander.golin@mongodb.com</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_11151" key="com.atlassian.jira.toolkit:LastCommentDate">
                        <customfieldname>Last public comment date</customfieldname>
                        <customfieldvalues>
                            3 years, 33 weeks, 2 days ago
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                    <customfield id="customfield_10051" key="com.atlassian.jira.toolkit:participants">
                        <customfieldname>Participants</customfieldname>
                        <customfieldvalues>
                                        <customfieldvalue>backlog-query-execution</customfieldvalue>
            <customfieldvalue>ian.boros@mongodb.com</customfieldvalue>
    
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                        <customfield id="customfield_14254" key="com.pyxis.greenhopper.jira:gh-lexo-rank">
                        <customfieldname>Product Rank</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>1|hxqtyn:</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                <customfield id="customfield_12550" key="com.pyxis.greenhopper.jira:gh-lexo-rank">
                        <customfieldname>Rank</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>2|hr2hqn:</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_10558" key="com.pyxis.greenhopper.jira:gh-global-rank">
                        <customfieldname>Rank (Obsolete)</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>9223372036854775807</customfieldvalue>
                        </customfieldvalues>
                    </customfield>
                                                                                            <customfield id="customfield_23361" key="com.onresolve.jira.groovy.groovyrunner:scripted-field">
                        <customfieldname>Requested By</customfieldname>
                        <customfieldvalues>
                                

                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    <customfield id="customfield_22870" key="com.onresolve.jira.groovy.groovyrunner:scripted-field">
                        <customfieldname>Triagers</customfieldname>
                        <customfieldvalues>
                                

                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                    <customfield id="customfield_14350" key="com.pyxis.greenhopper.jira:gh-lexo-rank">
                        <customfieldname>serverRank</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>1|hxqg7z:</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                    </customfields>
    </item>
</channel>
</rss>