Re: [ovirt-devel] Memory stats in VDSM

On 28 Aug 2017, at 13:37, Juan Hernández <jhernand(a)redhat.com&gt; wrote: On 08/28/2017 01:11 PM, Tomáš Golembiovský wrote: > Hi, > there is ongoing effort to change how VDSM collects information about > memory usage from guests. We used to use oVirt guest agent to get the > statistics about free memory, swap usage, etc. This is going to change > and we will use stats provided by VirtIO Balloon driver. [1] This should > not break MOM nor Engine (current or previous versions). > There is however small downside to this change. We will not be able to > fetch information about buffers and caches on Linux guests anymore > (mem_cached and mem_buffers in memoryStats). The corollary of this is > that free memory reported by Engine will also no longer include those > statistics and reported free memory will be really (only) free memory. > I now there will be mixed feelings about this and we would like to get > the information about buffers and caches back to the VDSM. Correctly via > balloon driver statistics. [2] This effort will however take some time. > Tomas > [1] https://gerrit.ovirt.org/#/q/topic:memory-stats > [2] https://lists.nongnu.org/archive/html/qemu-devel/2017-08/msg05239.html Note that this information is currently reported by the engine REST API, so it is part of its contract. Removing it breaks backwards compatibility and causes a regression in this RFE:

[RFE] Report guests Buffered/Cached memory https://bugzilla.redhat.com/1024010 _______________________________________________ Devel mailing list Devel(a)ovirt.org http://lists.ovirt.org/mailman/listinfo/devel