Date: Thu, 2 Mar 2000 11:18:36 +0200 (IST) From: Eli Zaretskii X-Sender: eliz AT is To: Kalum Somaratna aka Grendel cc: djgpp AT delorie DOT com Subject: Re: rhide compile.. In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Reply-To: djgpp AT delorie DOT com Errors-To: dj-admin AT delorie DOT com X-Mailing-List: djgpp AT delorie DOT com X-Unsubscribes-To: listserv AT delorie DOT com Precedence: bulk On Wed, 1 Mar 2000, Kalum Somaratna aka Grendel wrote: > > SmartDrv flushes its buffers when a program exits, so it is slower > > than a RAM disk. > > This is the default behaviour of smatrdrv and is there for people who are > afraid that they might loose data because of write caching etc. > But if you add the /N option IIRC this will tell smartdrv not to flush the > write cache when the program exits. See my followups, they explain why /N is not what you think it is. > > > And there will be more efficient memory usage as there is no need to > > > allocate memory as in a ramdisk for the whole tool chain, for how many of > > > the tools do we actually use? > > > > If you have enough memory installed, this is not an issue. > > Actually how much should "enough" be? If you have 64MB or more installed, I don't think you should have problems with having a large SmartDrv cache and a fairly large RAM disk. > GCC itself hogs up a large amount of > memory and allocationg too much memory for a ramdisk will be > counterproductive as GCC will start paging to the hard disk. I have a 10MB cache and a 4MB RAM disk on a 64MB machine, and I have yet to see GCC paging, even though I mostly invoke it from Emacs, which itself gobbles upwards of 10MB of memory on a bright day. Of course, one can come up with a source which would cause GCC to page with *any* amount of memory. (Just a few days ago someone reported on the GCC mailing list that a certain code line caused GCC to allocate 500MB of memory.) The question is, how frequently do these pathological cases happen to warrant changes in system configuration. Punishing 99.99% of compiles because of the naughty 0.01% is not wise, IMHO. > FWIW I find that a 8mb smartdrv with write caching enabled and the /N > switch works marvels and is far easier to setup than a RAMDISK. Try adding a 2MB RAM disk on top of that, point TMPDIR to it, and see the effect. Setup problem? What setup problems? There are no setup problems ;-).