在命令行检查mac os的系统状态

浅浅的花香味﹌ 2022-08-27 03:21 118阅读 0赞

So I'm logging into a Mac OS X machine (Server or not) remotely by ssh to do some maintenance and check on the health of the system. What I might be interested in is how CPU, memory and disk usage is coping with the jobs the server has to do. If I was sitting in front of the machine I could open "Activity Monitor" and click my way through the GUI. Not an option for this machine, since there is no GUI level remote access. So what do I do? There are some command line tools to give me the information I need, let me show you top, vm\_stat and iostat... On my OpenBSD box "systat vmstat" is what I use for a full overview. That is not available for OS X, but some other tools are there. Most often used is "top", followed by "vm\_stat" and "iostat". top "top" is well known and you likely have heard about it and probably used it before. The version on OS X is quite useable. After switching to "compatibility mode" (with 'x'), one can see only the processes of a single user (with 'U' and entering the user id or name). Top is good for checking what eats all the CPU time. vm\_stat If it comes to memory usage, especially for the question "how much swap space am I using", then vm\_stat can help. On Mac OS X that's vm\_stat with an underscore, not vmstat. You just give vm\_stat a delay in seconds (by calling it like "vm\_stat 10" on the command line) and it updates the display repeatedly. Go on, try that out and then open a bunch of applications to see if pageouts are going up (which would mean that your machine has to page memory out on disk to make room for the new ones). $ vm\_stat 5 Mach Virtual Memory Statistics: (page size of 4096 bytes, cache hits 58%) free active inac wire faults copy zerofill reactive pageins pageout 49314 97619 154001 26746 42361341 320895 24148787 145786 50308 3459 49341 97814 153974 26551 2902 21 1429 0 0 0 45297 98409 157246 26728 12056 805 5639 0 272 0 40400 101288 158727 27265 14663 841 6746 0 1261 0 36365 103524 160004 27787 8302 712 3519 0 1630 0 ...looks like my workstation is OK, even with starting up Acrobat Reader and a bunch of smaller programs at once. iostat It took me longer to discover iostat. The man page says that "Iostat displays kernel I/O statistics on terminal, device and cpu operations." Which is quite a lot and probably more than I usually want. I just use it with a line like: iostat -d -K -w 5 to show me only devices (-d), kilobytes instead of blocks (-K), and have a wait interval of 5 seconds (-w 5). Go ahead, try it and watch it while doing a find for "foobar" on your disks. As usual with all command line tools, read the fine man pages. $ iostat -d -K -w 5 disk0 KB/t tps MB/s 16.90 1 0.01 31.79 131 4.07 32.00 752 23.51 32.00 35 1.10 4.00 1 0.00 0.00 0 0.00 ^C Finding all files that start with "pimp" on my single disk got the activity up a bit, then I stopped it with control-C. The display shows me Kilobytes per transfer, transfers per second, and Megabytes per second. Interpretation is of course up to you not to the tool :-). Playing with the -I switch might be interesting.