From mboxrd@z Thu Jan 1 00:00:00 1970 From: George Dunlap Subject: Re: [PATCH v2 0/2] xentrace: Add TRC_HVM_VCHIP (was xentrace: Add TRC_HW_VCHIP). Date: Tue, 1 Apr 2014 17:01:39 +0100 Message-ID: <533AE2E3.2060007@eu.citrix.com> References: <1396025767-3430-1-git-send-email-dslutz@verizon.com> <533AB9C8.309@eu.citrix.com> <533AD8BA.3050101@terremark.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <533AD8BA.3050101@terremark.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: Don Slutz , xen-devel@lists.xen.org, Jan Beulich , Tim Deegan Cc: Keir Fraser , Ian Jackson , Ian Campbell , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org On 04/01/2014 04:18 PM, Don Slutz wrote: > On 04/01/14 09:06, George Dunlap wrote: >> On 03/28/2014 04:56 PM, Don Slutz wrote: >>> Changes v1 to v2: >>> Tim Deegan: >>> Switch from TRC_HW_VCHIP to TRC_HVM_VCHIP. >>> Drop get_cycles() >>> Fix coding style issues. >>> Drop code that should not have been included. >>> Use names not numbers. >>> >>> Split in 2 patches for simpler review. >>> >>> Here is a subset of sample output: >> >> Are you aware of xenalyze? It's got a lot of advantages over >> xentrace_format; the most basic of which is that it traces vcpus as >> they run across pcpus. >> > > I have noticed that it exists. Not sure it would help with the issue I > was looking into. > > I have determined that I would see: > > CPU5 841028423232 (+ 3900) hpet create [ tn = 0, irq = 0, delta = > 68718266336, period = 1000000 ] > > If I had been able to reproduce my issue. Sure; but if you ever need to track a vcpu as it moves across pcpus, or see how the interaction of two vcpus cause an issue that you're seeing, xentrace_format isn't going to help you. Additionally, with xenalyze it's a lot easier to add ad-hoc warnings or statistics gathering patches. > > Do I need to make a change there also? If you want to use xenalyze to analyze your traces, it would probably make it a lot easier. :-) (xenalyze will dump records it doesn't recognize in a sort of binary format, but that's probably not what you want.) As it's out-of-tree, there's certainly no *requirement* for you to make a change there as a follow-up to this series. -George