<?xml version="1.0" encoding="UTF-8"?>
<rss xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:taxo="http://purl.org/rss/1.0/modules/taxonomy/" version="2.0">
  <channel>
    <title>topic Errors casuing unusable Indexer Linux VMs, slowdowns for entire vcenter cluster until powered off in Getting Data In</title>
    <link>https://community.splunk.com/t5/Getting-Data-In/Errors-casuing-unusable-Indexer-Linux-VMs-slowdowns-for-entire/m-p/496385#M84678</link>
    <description>&lt;P&gt;We are seeing two types of dmesg errors on the linux VMs which are acting as our indexers:&lt;/P&gt;

&lt;P&gt;1) “task blocked for more than 120 seconds, hung_task_timeout_secs, call trace” - &lt;A href="https://del.dog/120blk.txt" target="_blank"&gt;https://del.dog/120blk.txt&lt;/A&gt;&lt;/P&gt;

&lt;P&gt;2) “sd 0:0:0:0: [sda] task abort on host 0” - &lt;A href="https://del.dog/tskabrt.txt" target="_blank"&gt;https://del.dog/tskabrt.txt&lt;/A&gt;&lt;/P&gt;

&lt;P&gt;These issues seem to be also causing high I/O for all VMs on the same vcenter cluster that the indexers are on. As soon as we get the indexers powered down, performance is restored across the cluster.&lt;/P&gt;

&lt;P&gt;Things I've tried:&lt;BR /&gt;
-Full yum update&lt;BR /&gt;
-Disabling Huge Pages&lt;BR /&gt;
-Tried booting with older kernel two versions back, and latest ones.&lt;BR /&gt;
-Initially we were on RDM backed by EMC VNX SAN for hot space. This was converted to VMDK (still backed by VNX).&lt;BR /&gt;
-Initially the hot drives were thin. They were converted to Eager Thick.&lt;BR /&gt;
-Initially the hot drives were formatted with XFS. I have migrated them to EXT4.&lt;BR /&gt;
-I tried tuning system cacheing / flushes per this explanation: &lt;A href="https://www.blackmoreops.com/2014/09/22/linux-kernel-panic-issue--fix-hung_task_timeout_secs-blocked-120-seconds-problem/" target="_blank"&gt;https://www.blackmoreops.com/2014/09/22/linux-kernel-panic-issue--fix-hung_task_timeout_secs-blocked-120-seconds-problem/&lt;/A&gt;&lt;/P&gt;</description>
    <pubDate>Wed, 30 Sep 2020 05:24:05 GMT</pubDate>
    <dc:creator>mevangelisti</dc:creator>
    <dc:date>2020-09-30T05:24:05Z</dc:date>
    <item>
      <title>Errors casuing unusable Indexer Linux VMs, slowdowns for entire vcenter cluster until powered off</title>
      <link>https://community.splunk.com/t5/Getting-Data-In/Errors-casuing-unusable-Indexer-Linux-VMs-slowdowns-for-entire/m-p/496385#M84678</link>
      <description>&lt;P&gt;We are seeing two types of dmesg errors on the linux VMs which are acting as our indexers:&lt;/P&gt;

&lt;P&gt;1) “task blocked for more than 120 seconds, hung_task_timeout_secs, call trace” - &lt;A href="https://del.dog/120blk.txt" target="_blank"&gt;https://del.dog/120blk.txt&lt;/A&gt;&lt;/P&gt;

&lt;P&gt;2) “sd 0:0:0:0: [sda] task abort on host 0” - &lt;A href="https://del.dog/tskabrt.txt" target="_blank"&gt;https://del.dog/tskabrt.txt&lt;/A&gt;&lt;/P&gt;

&lt;P&gt;These issues seem to be also causing high I/O for all VMs on the same vcenter cluster that the indexers are on. As soon as we get the indexers powered down, performance is restored across the cluster.&lt;/P&gt;

&lt;P&gt;Things I've tried:&lt;BR /&gt;
-Full yum update&lt;BR /&gt;
-Disabling Huge Pages&lt;BR /&gt;
-Tried booting with older kernel two versions back, and latest ones.&lt;BR /&gt;
-Initially we were on RDM backed by EMC VNX SAN for hot space. This was converted to VMDK (still backed by VNX).&lt;BR /&gt;
-Initially the hot drives were thin. They were converted to Eager Thick.&lt;BR /&gt;
-Initially the hot drives were formatted with XFS. I have migrated them to EXT4.&lt;BR /&gt;
-I tried tuning system cacheing / flushes per this explanation: &lt;A href="https://www.blackmoreops.com/2014/09/22/linux-kernel-panic-issue--fix-hung_task_timeout_secs-blocked-120-seconds-problem/" target="_blank"&gt;https://www.blackmoreops.com/2014/09/22/linux-kernel-panic-issue--fix-hung_task_timeout_secs-blocked-120-seconds-problem/&lt;/A&gt;&lt;/P&gt;</description>
      <pubDate>Wed, 30 Sep 2020 05:24:05 GMT</pubDate>
      <guid>https://community.splunk.com/t5/Getting-Data-In/Errors-casuing-unusable-Indexer-Linux-VMs-slowdowns-for-entire/m-p/496385#M84678</guid>
      <dc:creator>mevangelisti</dc:creator>
      <dc:date>2020-09-30T05:24:05Z</dc:date>
    </item>
    <item>
      <title>Re: Errors casuing unusable Indexer Linux VMs, slowdowns for entire vcenter cluster until powered off</title>
      <link>https://community.splunk.com/t5/Getting-Data-In/Errors-casuing-unusable-Indexer-Linux-VMs-slowdowns-for-entire/m-p/516435#M87412</link>
      <description>&lt;P&gt;Is it helpful to resolve this blocked issue with the two parameters?&lt;/P&gt;&lt;PRE&gt;vm.dirty_background_ratio = 5
vm.dirty_ratio = 10&lt;/PRE&gt;&lt;P&gt;&amp;nbsp;&lt;/P&gt;</description>
      <pubDate>Thu, 27 Aug 2020 05:44:05 GMT</pubDate>
      <guid>https://community.splunk.com/t5/Getting-Data-In/Errors-casuing-unusable-Indexer-Linux-VMs-slowdowns-for-entire/m-p/516435#M87412</guid>
      <dc:creator>williaml_splunk</dc:creator>
      <dc:date>2020-08-27T05:44:05Z</dc:date>
    </item>
  </channel>
</rss>

