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<div class="moz-text-flowed" style="font-family: -moz-fixed;
font-size: 14px;" lang="x-unicode">Hello,
<br>
<br>
For a very long time now (we're talking the past few years) I've
faced an issue with a number of my nodes where by two kswapd
processes fire up frequently (using ~200% CPU between them).
<br>
It's at those times that the overall load average shoots up (from
a normal range of 30-50 to 100+), resulting in temporary
performance degradation.
<br>
<br>
I'm currently using the latest stable kernel
(3.10.0-1160.21.1.vz7.174.13) with all available updates
installed, but have seen it on every other kernel in the past as
well.
<br>
<br>
There has been some suggestion from various people that upgrading
the amount of physical RAM would be beneficial, which doesn't make
a great deal of sense to me as there's always at least 30 GB RAM
available on the nodes, and 40 GB+ in most cases.
<br>
<br>
The node specifications are as follows:
<br>
<br>
2x Intel Xeon E5-2670v2
<br>
128 GB DDR3 ECC RAM (upgradable to 256 GB if needed)
<br>
4x 2 TB Samsung 870 SSD
<br>
Hardware RAID 10 w/ BBU (WriteBack, ReadAheadNone, Direct, No
Write Cache if Bad BBU)
<br>
<br>
Output from top -c: <a class="moz-txt-link-freetext"
href="https://i.imgur.com/C4Yo0V1.png">https://i.imgur.com/C4Yo0V1.png</a>
<br>
Output from free -m: <a class="moz-txt-link-freetext"
href="https://i.imgur.com/utkZNFf.png">https://i.imgur.com/utkZNFf.png</a>
<br>
<br>
My question is: has anyone seen anything like this? Is there
anything that I should consider doing to help remedy the problem?
Upgrading the RAM is an option, but I am not entirely convinced it
will be beneficial.
<br>
<br>
Many thanks.
<br>
<br>
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