Was there ever any software similar to system monitor for OS X for OS 9? I’m just curious at times how much processor is actually being used for example.
MacOS 9 and system monitors
- Thread starter KHEMISANTOS
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There's a couple nice process explorer tools the names of which currently escape me (not with my Macs at the moment), but I don't remember if they did CPU load. Difficult to do accurately in any case because classic Mac OS is cooperatively multitasked. An application that hogs the CPU, and many did (sometimes with good reason, sometimes not), will not let another app run, let alone figure out how many CPU cycles are available. Even under the preemptive multitasking feature available with Multiprocessing Services in 8.6+, whatever would actually display the CPU load would still be part of the blue task and subject to the usual cooperative limitations.
CPU usage is 100% for early macOS versions. Prior to pre-emptive scheduling, most things was polled for and so the processor was always busy. macOS 8 introduced pre-emption and multi-threading among some blocking system services, but applications still needed to co-operate!
It's instructive to run infinitemac.org in a modern machine's browser and use Activity Monitor to watch the emulation. It's accurate enough to see these behaviors.
It's instructive to run infinitemac.org in a modern machine's browser and use Activity Monitor to watch the emulation. It's accurate enough to see these behaviors.
Back on my MDD Mac. The tool I was thinking of is ProcessInfo.app: http://macintoshgarden.org/apps/processinfo-131
It does have CPU load and a nice graph, but remember, it won't necessarily be accurate if something pins the CPU.
It does have CPU load and a nice graph, but remember, it won't necessarily be accurate if something pins the CPU.
This is true, but one can measure which processes are using the CPU what % of the time, and do so accurately even if no process yields the CPU by checking (for example) the current application’s name 60 times/second from a VBL interrupt. It’s not actually very hard. That’s probably what apps like the one linked above did.
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I hadn't considered a VBL approach and I agree that makes things simpler, but if something's hogging the CPU, it should still need to yield to let the process monitor actually display anything, I would think.