Drew wrote: >FWIW, using a separate partition for VM storage won't speed VM up. >VM will just fragment the partition instead of your whole disk. Once >the partition is fragmented, VM will slow back down - I don't see any
A dedicated VM partition should never get fragmented, the swap file is one file, not many small files. >advantage here (beyond not fragmenting your data partitions). It >might be a good idea not to frag up the rest of your disk too hard >(fragmentation lengthens boot time and drive access time), but That's the point, the VM swap file need never interact with user files, _if_ on a separate volume. Then Victoria wrote: >>Aside from the fact that the very idea of a separate VM partition sounds too >>clever to ignore, if it's very small it can hardly get fragmented too badly. >>Or can it? And once fragged, can't it then be reformatted without going >>through all this nervewracking timeconsuming song and dance of redoing the >>whole drive? And then Drew wrote: > >Well, that sort of depends. Once you partition a disk, if you want >to reformat an individual partition using a Drive Setup, you have to >reformat the ENTIRE disk. Heck, we all do this all the time, in Finder - "Erase Disk". >IMO this is a major fault of drive setup, >but I understand it does this to protect the integrity of the >partition table. You can jump through hoops using 3rd party disk >formatters (or my favorite - pdisk) to format individual partitions... Integrity of partition tables? What the heck are you talking about here Drew? <BigGrin> >But what I believe you are thinking of is not re-formatting the >partition but optimizing or defragmenting it. You _can_ do that to >individual partitions without trouble. DiskWarrior does this >excellently. This is one of the big advantages of using a volume for VM _only_. If one _needs_ to defragment the volume, boot with extensions off and erase the volume in the Finder (can't erase it if VM is using it.) OTOH, I'm pretty darn sure the OS builds a new swap file at each startup, and the file isn't a bunch of scattered small files but one large contiguous file (assuming a clean VM partition.) If VM is on a dedicated partition, it doesn't have to dance around all the other clutter one creates during normal operations. >Here's a question for VM/disk drive gurus: If you decrease the >minimum block size from 4K to .5K under HFS+, will this speed up VM? >When VM reads from a drive, it reads a whole block at once. If the >blocks are smaller, will this speed it up? Good question that I'm sure's already been answered by somebody somewhere. I'll keep it in mind though and test it for myself next time I'm fooling about with an empty drive. How do block sizes affect throughput in other operations, such as Finder copies? The same principles may not be relevant with VM though and I haven't the foggiest idea how the classic Mac OS does reads/writes to its swap file. Dan K (who's proving to be just as stubborn as Drew!) : >) -- PowerBooks is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Enter To Win A | -- Canon PowerShot Digital Cameras start at $299 | Free iBook! | Support Low End Mac <http://lowendmac.com/lists/support.html> PowerBooks list info: <http://lowendmac.com/lists/powerbooks.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive: <http://www.mail-archive.com/powerbooks%40mail.maclaunch.com/> Using a Mac? Free email & more at Applelinks! http://www.applelinks.com
