| To: | "Rob Gardner" <rob.gardner@xxxxxx> |
|---|---|
| Subject: | Re: [Xen-devel] Hi,something about the xentrace tool |
| From: | "George Dunlap " <dunlapg@xxxxxxxxx> |
| Date: | 2006年6月15日 14:20:15 -0400 |
| Cc: | xen-tools@xxxxxxxxxxxxxxxxxxx, xen-devel@xxxxxxxxxxxxxxxxxxx, xen-users@xxxxxxxxxxxxxxxxxxx, rickey berkeley <rickey.berkeley@xxxxxxxxx> |
| Delivery-date: | 2006年6月15日 11:20:39 -0700 |
| Domainkey-signature: | a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=kFcw5Azihp4lzNmu4MM0NaRzlZGU9C+wbOnok6A4UNUpj4m1BayxXMMAE6OUKL+rFn7rC6WzEh4Td+TUijpj1YAfu/BNQu7kYEsqdWEEWF3TK2o4h4SuIn85V2erqwP+zyaltNLpCyo+Vgc3ukACY1lA+IZpgh50CS0PuR1t7nU= |
| Envelope-to: | www-data@xxxxxxxxxxxxxxxxxx |
| In-reply-to: | <449192E1.4080808@xxxxxx> |
| List-help: | <mailto:xen-devel-request@lists.xensource.com?subject=help> |
| List-id: | Xen developer discussion <xen-devel.lists.xensource.com> |
| List-post: | <mailto:xen-devel@lists.xensource.com> |
| List-subscribe: | <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe> |
| List-unsubscribe: | <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe> |
| References: | <A95E2296287EAD4EB592B5DEEFCE0E9D4BAAAA@xxxxxxxxxxxxxxxxxxxxxxxxxxx> <8061f8830606150158m35f11025t43c3fa962ccd6679@xxxxxxxxxxxxxx> <449192E1.4080808@xxxxxx> |
| Sender: | xen-devel-bounces@xxxxxxxxxxxxxxxxxxx |
On 6/15/06, Rob Gardner <rob.gardner@xxxxxx> wrote:
I wouldn't call the amount of data 'huge'. Even on a very busy system, where there are thousands of trace records being generated every second, that's still a pretty small amount of data. (The size of a trace record is something like 50 or 60 bytes.)
For the record, I think the trace record size in the trace buffers is
probably 32 bytes:
struct {
unsigned long long rdtsc; /* 8 */
unsigned long event; /* + 4 = 12 */
unsigned long data[5] /* + (4 * 5) = 32 */
};
The size on disk from xentrace is 36 bytes (it adds 4 bytes for the cpu).
If someone were really worried about copy time, one could write
something which uses raw disks (or, perhaps, the O_DIRECT flag) to DMA
data straight from the buffers to the disk. But I'm not really
worried about it at this point. :-)
Peace,
-George
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
| <Prev in Thread] | Current Thread | [Next in Thread> |
|---|---|---|
| ||
| Previous by Date: | [Xen-users] openmanage dcdbas , Mark Foster |
|---|---|
| Next by Date: | Re: [Xen-devel] Hi,something about the xentrace tool , Rob Gardner |
| Previous by Thread: | Re: [Xen-devel] Hi,something about the xentrace tool , Rob Gardner |
| Next by Thread: | Re: [Xen-devel] Hi,something about the xentrace tool , Rob Gardner |
| Indexes: | [Date] [Thread] [Top] [All Lists] |