iOS Simulator / XCode perf

Discussion in 'iOS Programming' started by moral-hazard, Oct 7, 2012.

  1. moral-hazard macrumors regular

    Jul 27, 2009
    Palo Alto, CA
    TL/DR: I'm running an older (but reasonably powerful/well-maintained) machine. XCode 4 and the iOS simulator make the machine sluggish and borderline unusable. Will upgrading to a new Mac Mini make it more responsive?

    I haven't been able to answer this with googling...

    XCode and the iPhone simulator are more or less crushing my machine's performance (2.26GHz C2D 13" MBP, in my sig). With XCode, things like opening a new tab have noticeable lag (1-3 seconds). The iOS simulator is the real killer -- both cores end up at around 40-90% utilization and the whole machine feels sluggish. Top/HTOP report that memory usage is close to 100% (but no swap space being used - so memory is likely not the culprit). Trying to click around web pages can be painful, and if I leave the simulator open my fans spin up like crazy and stay there. Adding instruments in to the mix to profile for memory leaks was more or less agonizing.

    I'm thinking of buying a new Mac Mini if they ever update, and fitting it with 16GB ram and an OWC SSD. My question is: will a newer machine even alleviate the problem? It seems like launching up the simulator eats up a good amount of CPU even on a reasonably powerful machine...since the Mini's are only dual core, I don't know that this will make a huge difference. I don't know what the bottleneck is here - it may even be graphics related, given that it's an old mobile chip powering a 30" ultrasharp monitor w/ the simulator running as well.

    Any thoughts? Thanks!
  2. Duncan C macrumors 6502a

    Duncan C

    Jan 21, 2008
    Northern Virginia

    My Core 2 duo (C2D) MacBook pro (early 2008) ran Xcode 4 quite well under Snow Leopard.

    Lion is an absolute dog on C2D machines. (Lion is a dog on any machine, but much worse on C2D machines) Mountain Lion is marginally better, but only marginally.

    Xcode 4.5 is usable on my C2D Macbook Pro, but just. I have 4 GB of RAM in it, which is a near requirement. Supposedly you can upgrade most of these older machines to 6 GB, but not 8 GB. 10.7 and 10.8 are much more memory hungry than 10.6, so put in as much RAM as you possibly can.

    10.8 and Xcode 4.5 run acceptably on my early 2008 8-core Xeon Mac Pro. Xcode still has multi-second long pregnant pauses when doing silly things like switching tabs. It also hangs or crashes at least every other day, sometimes more often.

    An i7 machine will definitely be significantly faster, but I don't expect the pregnant pauses to get must better. Those seem to be fundamental problems with the way Xcode 4.x is written.

Share This Page