Subject: Re: Is gcc slow? Or is our gcc slow?
To: None <current-users@NetBSD.ORG>
From: der Mouse <mouse@Collatz.McRCIM.McGill.EDU>
List: current-users
Date: 04/11/1996 14:32:20
>> Hm, self-tuning, that sounds like (a) a really cool idea and (b) a
>> maintenance nightmare when it goes wrong.  When will you have a
>> sample implementation ready for us to experiment with?

> Peter (petersv@df.lth.se) has sent you the answer yet.  He was
> talking about "AUTOGEN" of VMS which adjusts the system parameters
> with feedback data of the system (for the next reboot).

Um, how is that "a sample implementation" for NetBSD users?  I don't
have any hardware capable of running VMS even if I wanted to.

> Andrew's (gillhaa@ghost.whirlpool.com) measurement (make build
> with/without -pipe and MFS) did show, that -pipe decreases the real
> time to compile the sources.

For that particular system.

> It also shows that MFS decreases it more than -pipe.  I think that
> transfers via pipes are much more simple than transfers via a file
> system.

Conceptually, yes.  But when comparing -pipe versus MFS tempfiles
there's so much more than just the data transfer being compared; you're
being hit with context switching among the various pieces and
particularly with the paging caused thereby.

Unless, of course, you have enough core to keep all the processes
in-core at once...in which case yes, I recommend you use -pipe.
Unfortunately, many people are not so lucky.

					der Mouse

			    mouse@collatz.mcrcim.mcgill.edu