You might not have noticed this, but MailMate is still a 32 bit application. The main reason for that is not that it is technically hard to switch to 64 bit. The main reason is that memory usage would increase considerably if doing it naively. MailMate indexes a lot of data using data structures with a lot of address pointers. In fact, the first experimental 64 bit build of MailMate used almost twice the memory of the 32 bit build.

It is quite rare that users “complain” about MailMate being a 64 bit app, but there are many reasons that staying 32 bit is not a good idea. One of them is the fact that if MailMate is the only 32 bit app on your system then it uses a lot more memory than you might realize. This is because a 32 bit app triggers the system to load 32 bit system frameworks. On my system, MailMate, Spotify, and SpiderOak are the only 32 bit apps (Google Chrome very recently switched to 64 bit)1. Having MailMate on that list is becoming a bit of an embarrassment.

Now, you might have noticed the lack of beta/test releases of MailMate in the past month. This is because I’ve been working on a 64 bit release of MailMate. Most of that work has been focused on optimizations regarding both speed and memory. It’s hard to measure this in general, but on my system MailMate now launches 2-3 times faster than the 32 bit release and it uses less memory.

The 64 bit releases are on a separate auto-update system and I’ll keep it that way until I’m relatively sure it’s at least as stable as the latest 32 bit release. You can help me reach that milestone by switching to 64 bit now. Initially, it’ll require a manual install of this download. If needed, you can switch back to the 32 bit release.

Although the 64 bit release primarily features optimizations, it also includes a few new features, changes, and fixes. Here are some of the most interesting:

  • New: “Default Account” setting for new messages in the Composer preferences pane.
  • New: Completion of email addresses works for any contacts with a company name (and email address).
  • New: Added perform command to the AppleScript API. Its argument is a list of strings identical to what would be used to define a custom key binding. The frontmost window of MailMate is the target even if MailMate is not in focus (activated). Example: tell application "MailMate" to perform {"toggleFlag:"}
  • New: “Distortion Mode” now also works for HTML messages and attachment descriptions.

If you are new to MailMate then don’t miss the FAQ part of the previous blog post. Related to that, I really appreciate that the (somewhat low-key) mini crowd funding campaign has reached 25% of my initial goal.

  1. You can use the Activity Monitor in OS X if you want to see which applications are running in 32 bit mode (switch to the Memory pane on Yosemite). Click on the header of the column to sort the list.