From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: xl only waits 33 seconds for ballooning to complete Date: Wed, 7 Jan 2015 09:38:31 +0000 Message-ID: <1420623511.18631.1.camel@citrix.com> References: <3571466.tH85X1fGBO@linux-4w67.dnsdhcp.provo.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <3571466.tH85X1fGBO@linux-4w67.dnsdhcp.provo.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Mike Latimer Cc: xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On Tue, 2015-01-06 at 14:17 -0700, Mike Latimer wrote: > Hi, > > In a previous post (1), I mentioned issues seen while ballooning a large > amount of memory. In the current code, the ballooning process only has 33 > seconds to complete, or the xl operation (i.e. domain create) will fail. When > a lot of ballooning is required, or the host is very slow to balloon memory, > this delay is not sufficient. > > The code involved is tools/libxl/xl_cmdimpl.c:freemem. This function retries 3 > times, and each retry includes a 10 second delay in libxl_wait_for_free_memory > and a 1 second delay in libxl_wait_for_memory_target. > > Is there a better approach, which would account for ballooning operations that > take a much longer time to complete? > > The easiest option is to simply increase the retry count, but that would again > leave us with a fixed window of time for an operation to complete. It seems > like something that monitors the balloon process, and continues to wait if it > is progressing, might be a better approach. That's exactly what I was about to suggest as I read the penultimate paragraph, i.e. keep waiting so long as some reasonable delta occurs on each iteration. Ian. > > Any ideas? > > Thanks, > Mike > > 1. http://lists.xen.org/archives/html/xen-devel/2014-12/msg01443.html > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel