Speeding up the Time Machine

I've been wondering recently why Time Machine has been taking so long to do its hourly backups. For the most part, not a lot changes on this machine, yet the backups often take up to 20 mins (including the pre- and post-processing). This can slow the machine down a bit as both the internal and firewire disks grind away.

After a bit of investigation, I discovered a blog post which said that large mailboxes in Mail can slow down Time Machine. Aha! That makes sense - Apple switched to using a maildir-like format which means that all emails are stored as individual files. While this makes sense from an application performance perspective, it really slows down backups as it looks at each file. Being subscribed to quite a few mailing lists (including most of the major FreeBSD lists), I receive quite a lot of mail, so my mail folders are all very large - tens of thousands of messages in each folder - plus the main archive of my Inbox.

I store all of my mail on my IMAP server, so I decided to tell Time Machine not to bother backing up ~/Library/Mail anymore - et voila! Backups are now much faster - usually only a couple of minutes, or up to 10 when it's purging expired backups. This is much more reasonable.

Snow Leopard is not a minor update.

For those who aren't aware, Apple is due to be releasing the next version of Mac OS X in September - version 10.6, aka Snow Leopard.

Many websites seem to be describing Snow Leopard as a "minor update", hence Apple's decision to offer upgrades to existing Leopard users for just $29 rather than the usual $89. The simple truth of the matter is, Snow Leopard is not a minor update. Seriously. Sure, most end-users won't notice a difference, but that doesn't mean it's just a minor update. Plenty has changed under the hood. The coders at Apple have been hacking away converting everything to run 64-bit. There are lots of performance tweaks. Finder has been completely rewritten. Faster Time Machine. OpenCL. Grand Central Dispatch. All fantastic enhancements.

I'd say that all these changes do warrant a major release. Snow Leopard is looking like it's going to be a fantastic release (and hopefully the most stable .0 yet!), so please, all of you who keep insisting that it's "just a minor release", please stop!