cloudstack-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Riepl, Gregor (SWISS TXT)" <Gregor.Ri...@swisstxt.ch>
Subject Re: KVM host AvailableMemory data is incorrect
Date Wed, 15 Jul 2020 09:41:21 GMT
This sounds very familiar...

https://bugzilla.redhat.com/show_bug.cgi?id=1250060
and they rolled it back in
https://bugzilla.redhat.com/show_bug.cgi?id=1779609
because upstream didn't accept their patch.

We had to "fix" our memory monitoring twice because of this.

It's important to *not* calculate buffer/cache memory towards memory usage, because the kernel
can reclaim this memory whenever there is a need.
________________________________
From: li jerry <div8cn@hotmail.com>
Sent: 15 July 2020 08:27
To: users@cloudstack.apache.org <users@cloudstack.apache.org>
Subject: KVM host AvailableMemory data is incorrect

Hello everyone
     We use HCI to run CloudStack (KVM+CEPH). After running for a period of time, cloudstack
reports that HOST has no available memory. But ZABBIX monitoring shows that HOST still has
a lot of available memory. By observing /proc/meminfo on KVM HOST, it is found that most of
the memory is occupied by Buffers.

     Further analysis of the source code of cloudstack-agent shows that the algorithm for
cloudstack-agent to obtain AvailableMemory on the host is:

Cached +MemFree -reservedMemory +overCommitMemory

It does not calculate the memory occupied by Buffers.


Excuse me, can I mark the memory occupied by Buffers as AvailableMemory?

If not, what is the reason?

Thank you!


-       Jerry

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message