Andrew Morton wrote:
Shailabh Nagar <[email protected]> wrote:
delayacct-virtcpu.patch
Distinguish between "wall-clock" and "virtual" cpu run times and return
both, at per-task and per-tgid granularity.
Some architectures adjust tsk->utime+tsk->stime to reflect the time that
the kernel wasn't scheduled in hypervised environments and this is the
"wall-clock" cpu run time. "Virtual" cpu run time, on the other hand, does
not account for the kernel being descheduled.
This patch allows the most accurate "virtual" cpu run time, collected by
the schedstats code (now shared with delay accounting code), to be returned
to user space, in addition to the "wall-clock" cpu time that was being exported
earlier. Both these times are useful for workload management in different
situations.
In a non-virtualized environment, or on architectures which do not adjust
tsk->utime/stime, these will effectively be the same value but at different
granularities.
...
Index: linux-2.6.16/include/linux/taskstats.h
===================================================================
--- linux-2.6.16.orig/include/linux/taskstats.h 2006-03-29 18:13:18.000000000 -0500
+++ linux-2.6.16/include/linux/taskstats.h 2006-03-29 18:13:20.000000000 -0500
@@ -46,8 +46,14 @@ struct taskstats {
__u64 swapin_count;
__u64 swapin_delay_total; /* swapin page fault wait*/
- __u64 cpu_run_total; /* cpu running time
- * no count available/provided */
+ __u64 cpu_run_real_total; /* cpu "wall-clock" running time
+ * Potentially accounts for cpu
+ * virtualization, on some arches
+ */
+ __u64 cpu_run_virtual_total; /* cpu "virtual" running time
+ * Uses time intervals as seen by
+ * the kernel
+ */
};
Again, the reader of this struct wants to know what the atomicity rules are.
Will add comment.
+ d->cpu_run_real_total = (tmp < (nsec_t)d->cpu_run_real_total)? 0: tmp;
lval = expr1 ? expr2 : expr3;
didn't get whats wrong ?
+ tmp = (nsec_t)d->cpu_run_virtual_total
+ + (nsec_t)jiffies_to_usecs(t3) * 1000;
umm, Linux doesn't have nsec_t any more.
Ok, will switch to s64 everywhere.
--Shailabh
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
