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14

You can use tstime to measure the highwater memory usage (RSS and virtual) of a process. For example: $ tstime date Tue Aug 16 21:35:02 CEST 2011 Exit status: 0 pid: 31169 (date) started: Tue Aug 16 21:35:02 2011 real 0.017 s, user 0.000 s, sys 0.000s rss 888 kb, vm 9764 kb It also supports a more easy to parse ...


11

time is a built-in of your shell. If you like time but need more information, try GNU time. /usr/bin/time -v sleep 5 Command being timed: "sleep 5" User time (seconds): 0.00 System time (seconds): 0.00 Percent of CPU this job got: 0% Elapsed (wall clock) time (h:mm:ss or m:ss): 0:05.00 Average shared text size ...


9

I don't think you can, easily, tell it "temporarily stop caching". But what you can do is tell the system to drop the cache before each run: As root: sync; echo 3 > /proc/sys/vm/drop_caches (This is documented in the kernel docs at Documentation/sysctl/vm.txt, which is handy if like some of us you can't always remember offhand what the values 1, 2, or ...


9

Maybe overkill, but I just found that valgrind has a nice tool named massif. I tested it on xterm: valgrind --trace-children=true --tool=massif xterm ms_print massif.out.* | less And you obtain a nice memory usage graph: MB 4.230^ # ::::::: ::: @@: ::: | @ #:::@::@@:::::@::::::: ...


8

Maybe setup smokeping on the Linux side, and point it at your AP? Smokeping will periodically (configurable) send -20 pings at the same time, and then graph how how many returned and the range of times that they returned in. If you have a lot of dropped packets, or the really wide range, then you should be concerned. If you want to run smokeping you ...


7

You did not specify which operating system you use. Linux Instead of using time foo which is (usually) a shell built-in you could try the external command /usr/bin/time foo. It gives some additional information such as number of file system inputs and outputs (but no information about cache hits or byte amounts). See man time and man getrusage for further ...


7

Not sure if you're looking for tools that show this type of information in a real-time type of way or over a period of time, but here are 2 tools that show the real-time aspects of the disk being accessed. nmon You invoke it like so, nmon. Then once it's open you hit the j (Filesystems) followed by a d (Disk I/O Graphs D=Stats). See the built-in help (h) ...


4

You can use the shell builtin time. Just write it in front of the usual command like: time make.


3

The ratio (rkB/s + wkB/s)/%util of the iostat -x output should give you some insight: Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sda 0.04 3.65 7.16 6.37 150.82 212.38 53.71 0.03 1.99 0.82 3.31 0.76 1.03 I'm not sure how exactly this ratio corresponds to the disk seek. ...


3

Looks like tstime doesn't work anymore under non-root under Linux >=3.0. Here's a polling utility I wrote to hack around the issue: https://github.com/jhclark/memusg/blob/master/memusg


2

Use tcpdump to capture packets that are leaving your local LAN subnet. Then use tools like Wireshark or tshark to do some analysis on how much loss you're experiencing, as well as what the variance in round trip time is, and how TCP is behaving. (Windowing, retransmits, etc). The reason I suggest this rather than running some sort of ping/traceroute based ...


1

When you're lagging, use mtr to check the connection to the server. mtr is a traceroute program on steroids. It runs a continuous traceroute and generates meaningful network statistics such as % of lost packets and several RTT metrics. Statistics are generated for each link between you and the selected endpoint. Any links that exhibit a high Loss% or ...


1

When timing things like this I usually run it first to prime the cache. Then run the command using time. In testing something like this you should be more concerned about CPU and elapsed times, and less concerned about I/O time. In any case it is difficult to get fully accurate timings. If the input files exceed the size of memory available for buffers, ...



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