<!-- 
RSS generated by JIRA (9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66) at Thu Feb 08 03:48:25 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-18677] Throughput drop during transaction pinned phase of checkpoints under WiredTiger (larger data set)</title>
                <link>https://jira.mongodb.org/browse/SERVER-18677</link>
                <project id="10000" key="SERVER">Core Server</project>
                    <description>&lt;ul&gt;
	&lt;li&gt;132 GB memory, 32 processors, slowish SSDs, 20 GB WT cache&lt;/li&gt;
	&lt;li&gt;YCSB 10 fields/doc, 50/50 workload (zipfian distribution), 20 threads&lt;/li&gt;
	&lt;li&gt;data set size varies - see tests below
	&lt;ul&gt;
		&lt;li&gt;10M docs, data set ~12 GB (but cache usage can be double that)&lt;/li&gt;
		&lt;li&gt;20M docs, data set ~23 GB (but cache usage can be double that)&lt;/li&gt;
	&lt;/ul&gt;
	&lt;/li&gt;
&lt;/ul&gt;


&lt;p&gt;In &lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-18315&quot; title=&quot;Throughput drop during transaction pinned phase of checkpoints under WiredTiger&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-18315&quot;&gt;&lt;del&gt;SERVER-18315&lt;/del&gt;&lt;/a&gt; an issue was reported in 3.0.2 during the &quot;transaction pinned&quot; phase of checkpoints (B-C) with a 10M document data set:&lt;/p&gt;

&lt;p&gt;&lt;span class=&quot;image-wrap&quot; style=&quot;&quot;&gt;&lt;img src=&quot;https://jira.mongodb.org/secure/attachment/75877/75877_try-33.png&quot; width=&quot;900&quot; style=&quot;border: 0px solid black&quot; /&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p&gt;This was fixed in 3.1.3:&lt;/p&gt;

&lt;p&gt;&lt;span class=&quot;image-wrap&quot; style=&quot;&quot;&gt;&lt;img src=&quot;https://jira.mongodb.org/secure/attachment/75879/75879_try-52.png&quot; width=&quot;900&quot; style=&quot;border: 0px solid black&quot; /&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p&gt;However if the data set is increased to 20M documents a similar problem still appears in 3.1.3. Based on the shapes of the curves it appears this may be a little different issue: in &lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-18315&quot; title=&quot;Throughput drop during transaction pinned phase of checkpoints under WiredTiger&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-18315&quot;&gt;&lt;del&gt;SERVER-18315&lt;/del&gt;&lt;/a&gt; the throughput dropped in proportion to the rise in &quot;range of transactions pinned&quot; but that does not seem to be the case here.&lt;/p&gt;

&lt;p&gt;&lt;span class=&quot;image-wrap&quot; style=&quot;&quot;&gt;&lt;img src=&quot;https://jira.mongodb.org/secure/attachment/75878/75878_try-49a.png&quot; width=&quot;900&quot; style=&quot;border: 0px solid black&quot; /&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p&gt;(Note: C-D is a different issue - see &lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-18674&quot; title=&quot;Very low throughput during portion of checkpoint under WiredTiger&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-18674&quot;&gt;&lt;del&gt;SERVER-18674&lt;/del&gt;&lt;/a&gt;).&lt;/p&gt;</description>
                <environment></environment>
        <key id="206780">SERVER-18677</key>
            <summary>Throughput drop during transaction pinned phase of checkpoints under WiredTiger (larger data set)</summary>
                <type id="1" iconUrl="https://jira.mongodb.org/secure/viewavatar?size=xsmall&amp;avatarId=14703&amp;avatarType=issuetype">Bug</type>
                                            <priority id="3" iconUrl="https://jira.mongodb.org/images/icons/priorities/major.svg">Major - P3</priority>
                        <status id="6" iconUrl="https://jira.mongodb.org/images/icons/statuses/closed.png" description="The issue is considered finished, the resolution is correct. Issues which are closed can be reopened.">Closed</status>
                    <statusCategory id="3" key="done" colorName="success"/>
                                    <resolution id="9">Done</resolution>
                                        <assignee username="david.hows">David Hows</assignee>
                                    <reporter username="bruce.lucas@mongodb.com">Bruce Lucas</reporter>
                        <labels>
                    </labels>
                <created>Wed, 27 May 2015 15:23:58 +0000</created>
                <updated>Thu, 14 Apr 2016 15:19:16 +0000</updated>
                            <resolved>Thu, 16 Jul 2015 02:53:44 +0000</resolved>
                                    <version>3.1.3</version>
                                                    <component>WiredTiger</component>
                                        <votes>0</votes>
                                    <watches>8</watches>
                                                                                                                <comments>
                            <comment id="967471" author="david.hows" created="Thu, 16 Jul 2015 03:00:49 +0000"  >&lt;p&gt;Marking this as Done based on my testing, as I was unable to reproduce.&lt;/p&gt;

&lt;p&gt;There have been a number of changes to related parts of MongoDB and WT including the linked &lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-18875&quot; title=&quot;Oplog performance on WT degrades over time after accumulation of deleted items&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-18875&quot;&gt;&lt;del&gt;SERVER-18875&lt;/del&gt;&lt;/a&gt;, &lt;a href=&quot;https://jira.mongodb.org/browse/SERVER-18829&quot; title=&quot;Cache usage exceeds configured maximum during index builds under WiredTiger&quot; class=&quot;issue-link&quot; data-issue-key=&quot;SERVER-18829&quot;&gt;&lt;del&gt;SERVER-18829&lt;/del&gt;&lt;/a&gt; and &lt;a href=&quot;https://jira.mongodb.org/browse/WT-1907&quot; title=&quot;Speed up transaction-refresh&quot; class=&quot;issue-link&quot; data-issue-key=&quot;WT-1907&quot;&gt;&lt;del&gt;WT-1907&lt;/del&gt;&lt;/a&gt;. Suspect that some combination of those resolved the underlying issue.&lt;/p&gt;
</comment>
                            <comment id="966349" author="david.hows" created="Wed, 15 Jul 2015 03:00:20 +0000"  >&lt;p&gt;Ran this on an r3.4xlarge using Bruce&apos;s setup and MongoDB master as at 15/7/2015 Hash: 3f301ac62e&lt;/p&gt;

&lt;p&gt;The instance had a generic (slow) SSD storage formatted using XFS.&lt;/p&gt;

&lt;p&gt;With the 10M workload there was no drop in throughput associated with pinned transaction IDs due to a checkpoint. There was only one small drop in query throughput and this was associated with an increase in writes (update ops).&lt;/p&gt;

&lt;p&gt;With the 20M workload there was no instance when a trasnaction ID was pinned due to a checkpoint. There were no sustained drops in throughput&lt;/p&gt;</comment>
                            <comment id="958091" author="michael.cahill" created="Mon, 6 Jul 2015 02:33:31 +0000"  >&lt;p&gt;&lt;a href=&quot;https://jira.mongodb.org/secure/ViewProfile.jspa?name=david.hows&quot; class=&quot;user-hover&quot; rel=&quot;david.hows&quot;&gt;david.hows&lt;/a&gt; can you please retest against MongoDB master?&lt;/p&gt;</comment>
                    </comments>
                <issuelinks>
                            <issuelinktype id="10012">
                    <name>Related</name>
                                            <outwardlinks description="related to">
                                        <issuelink>
            <issuekey id="209236">SERVER-18875</issuekey>
        </issuelink>
            <issuelink>
            <issuekey id="208369">SERVER-18829</issuekey>
        </issuelink>
            <issuelink>
            <issuekey id="200653">WT-1907</issuekey>
        </issuelink>
                            </outwardlinks>
                                                                <inwardlinks description="is related to">
                                        <issuelink>
            <issuekey id="201914">SERVER-18315</issuekey>
        </issuelink>
            <issuelink>
            <issuekey id="206745">SERVER-18674</issuekey>
        </issuelink>
                            </inwardlinks>
                                    </issuelinktype>
                    </issuelinks>
                <attachments>
                            <attachment id="75877" name="try-33.png" size="63765" author="bruce.lucas@mongodb.com" created="Wed, 27 May 2015 15:23:58 +0000"/>
                            <attachment id="75878" name="try-49a.png" size="86308" author="bruce.lucas@mongodb.com" created="Wed, 27 May 2015 15:23:58 +0000"/>
                            <attachment id="76287" name="try-49b.png" size="246077" author="bruce.lucas@mongodb.com" created="Sat, 30 May 2015 14:37:05 +0000"/>
                            <attachment id="75879" name="try-52.png" size="101161" author="bruce.lucas@mongodb.com" created="Wed, 27 May 2015 15:23:58 +0000"/>
                            <attachment id="76288" name="try-64-gdb.png" size="575895" author="bruce.lucas@mongodb.com" created="Sat, 30 May 2015 14:37:05 +0000"/>
                    </attachments>
                <subtasks>
                    </subtasks>
                <customfields>
                                                <customfield id="customfield_10050" key="com.atlassian.jira.toolkit:comments">
                        <customfieldname># Replies</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>3.0</customfieldvalue>
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                                                                                                        <customfield id="customfield_10011" key="com.atlassian.jira.plugin.system.customfieldtypes:radiobuttons">
                        <customfieldname>Backwards Compatibility</customfieldname>
                        <customfieldvalues>
                                <customfieldvalue key="10038"><![CDATA[Fully Compatible]]></customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                                                                            <customfield id="customfield_10055" key="com.atlassian.jira.ext.charting:firstresponsedate">
                        <customfieldname>Date of 1st Reply</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>Tue, 2 Jun 2015 15:09:05 +0000</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_10052" key="com.atlassian.jira.toolkit:dayslastcommented">
                        <customfieldname>Days since reply</customfieldname>
                        <customfieldvalues>
                                        8 years, 31 weeks 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>ramon.fernandez@mongodb.com</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                <customfield id="customfield_11151" key="com.atlassian.jira.toolkit:LastCommentDate">
                        <customfieldname>Last public comment date</customfieldname>
                        <customfieldvalues>
                            8 years, 31 weeks ago
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                    <customfield id="customfield_10032" key="com.atlassian.jira.plugin.system.customfieldtypes:select">
                        <customfieldname>Operating System</customfieldname>
                        <customfieldvalues>
                                <customfieldvalue key="10026"><![CDATA[ALL]]></customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                <customfield id="customfield_10051" key="com.atlassian.jira.toolkit:participants">
                        <customfieldname>Participants</customfieldname>
                        <customfieldvalues>
                                        <customfieldvalue>bruce.lucas@mongodb.com</customfieldvalue>
            <customfieldvalue>david.hows</customfieldvalue>
            <customfieldvalue>michael.cahill@mongodb.com</customfieldvalue>
    
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                        <customfield id="customfield_14254" key="com.pyxis.greenhopper.jira:gh-lexo-rank">
                        <customfieldname>Product Rank</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>1|hrl4uv:</customfieldvalue>

                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                <customfield id="customfield_12550" key="com.pyxis.greenhopper.jira:gh-lexo-rank">
                        <customfieldname>Rank</customfieldname>
                        <customfieldvalues>
                            <customfieldvalue>2|hs9qb3:</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_10053" key="com.atlassian.jira.ext.charting:timeinstatus">
                        <customfieldname>Time In Status</customfieldname>
                        <customfieldvalues>
                            
                        </customfieldvalues>
                    </customfield>
                                                                                                                                                                                                                                                                                                                                                                                                                                                                        <customfield id="customfield_22870" key="com.onresolve.jira.groovy.groovyrunner:scripted-field">
                        <customfieldname>Triagers</customfieldname>
                        <customfieldvalues>
                                    <customfieldvalue><![CDATA[bruce.lucas@mongodb.com]]></customfieldvalue>
    

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

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