On 09/19/2013 05:35 AM, Mark Davies wrote: > I have a system that is (sometimes) used as an ftp server to serve g4u > disk images. Current machine is a Dell PowerEdge R320 with 16GB > memory running 6.1_STABLE from yesterday. > > If I get 3 ftp clients all reading the same 45GB image from it I > quickly get into the situation that all memory is used by something > and the machine becomes very unresponsive. Below is the output of top > while in this state: > > load averages: 3.38, 1.56, 0.68; up 0+16:11:05 > > 14:51:52 > 43 processes: 2 runnable, 38 sleeping, 3 on CPU > CPU0 states: 0.0% user, 0.0% nice, 23.6% system, 0.0% interrupt, > 76.4% idle > CPU1 states: 0.0% user, 0.0% nice, 4.1% system, 0.0% interrupt, > 95.9% idle > CPU2 states: 0.0% user, 0.0% nice, 28.5% system, 0.0% interrupt, > 71.5% idle > CPU3 states: 0.0% user, 0.0% nice, 2.1% system, 0.0% interrupt, > 97.9% idle > CPU4 states: 0.0% user, 0.0% nice, 3.8% system, 0.0% interrupt, > 96.2% idle > CPU5 states: 0.0% user, 0.0% nice, 78.9% system, 0.0% interrupt, > 21.1% idle > Memory: 15G Act, 113M Inact, 15M Wired, 29M Exec, 15G File, 112K Free > Swap: 8192M Total, 8192M Free > > PID USERNAME PRI NICE SIZE RES STATE TIME WCPU CPU > COMMAND > 0 root 126 0 0K 29M CPU/1 3:37 99.76% 99.76% > [system] > 7173 root 79 0 53M 4588K CPU/2 1:52 36.13% 36.13% > ftpd > 6931 root 113 0 53M 4588K RUN/2 1:13 28.42% 28.42% > ftpd > 7025 root 115 0 53M 4588K RUN/1 2:03 26.61% 26.61% > ftpd > 6601 root 43 0 17M 1876K CPU/5 0:01 4.05% 4.05% top > > > If I just run two ftp clients there seems to be about 5GB of Inactive > memory and performance is "fine". > > Previously I had an i386 box running 5.x or 6.x doing this job and it > could quite happily have 10-15 clients slurping images at once. > > So whats going on? > > cheers > mark >
Can you see which kernel thread causes high CPU usage by showing lwps in top? (t toggles those modes) Lars -- ------------------------------------ Mystische Erklärungen: Die mystischen Erklärungen gelten für tief; die Wahrheit ist, dass sie noch nicht einmal oberflächlich sind. -- Friedrich Nietzsche [ Die Fröhliche Wissenschaft Buch 3, 126 ]
