From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: [RFC][PATCH] 1/3] [XEN] Use explicit bit sized fields for exported xentrace data. Date: Thu, 30 Nov 2006 17:03:26 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: George Dunlap , Tony Breeds Cc: Xen-devel List-Id: xen-devel@lists.xenproject.org On 30/11/06 16:58, "George Dunlap" wrote: > Hmm... this has the unfortunate side-effect of doubling the size of > the trace, and effectively halving the effectiveness of the trace > buffer in avoiding drops. My moderate-length traces are already in > the gigabyte range, and I occasionally lose trace records even with a > buffer size of 256. It would be really nice if we could avoid that. > > I happen to be using the VMENTER/VMEXIT tracing, which could be > consolidated into one record if we went to a 64-bit trace. Is anyone > else doing high-bandwidth tracing that this would affect in a > significantly negative way? As we move increasingly towards x86/64 this is an issue that will need to be addressed even if we leave the tracing fields as longs. -- Keir