Re: DTrace-like analysis possible with future Linux kernels?

Timothy Miller
2004-09-01T00:48:55Z

Julien Oster wrote:
> Miles Lane <miles.lane@comcast.net> writes:
>
>
>>http://www.theregister.co.uk/2004/07/08/dtrace_user_take/:
>>"Sun sees DTrace as a big advantage for Solaris over other versions of Unix
>>and Linux."
>
>
> That article is way too hypey.
>
> It sounds like one of those strange american commercials you see
> sometimes at night, where two overenthusiastic persons are telling you
> how much that strange fruit juice machine has changed their lives,
> with making them loose 200 pounds in 6 days and improving their
> performance at beach volleyball a lot due to subneutronic antigravity
> manipulation. You usually can't watch those commercials for longer
> than 5 minutes.
>
> The same applies to that article, I couldn't even read it completely,
> it was just too much.
>
> And is it just me or did that article really take that long to
> mentioning what dtrace actually IS?
>
> Come on, it's profiling. As presented by that article, it is even more
> micro optimization than one would think. What with tweaking the disk
> I/O improvements and all... If my harddisk accesses were a microsecond
> more immediate or my filesystem giving a quantum more transfer rate,
> it would be nice, but I certainly wouldn't get enthusiastic and I bet
> nobody would even notice.
>
> Maybe, without that article, I would recognize it as a fine thing (and
> by "fine" I don't mean "the best thing since sliced bread"), but that
> piece of text was just too ridiculous to take anything serious.
>
> I sure hope that article is meant sarcastically. By the way, did I
> miss something or is profiling suddenly a new thing again?
>

[I have 4000 emails from lkml to read, so please forgive me if this
discussion is dead.]

DTrace was exactly what we needed here to figure out what was making our
E450 server perform so badly. We managed to find and eliminate all
sorts of bottlenecks, and now, all of our NFS activity is CPU bound on
the server.

Perhaps Linux never suffers from these sorts of problems that require
tuning things such as inode cache sizes, etc???