Hi James, I am not sure whether i have to add more RAM or change the disk we are using for caching. I am using normal SATA (7k rpm) as raw disk for caching.
Should I change it to SAS or SSD? Anyone is using RAMDISK for caching as disk? Or I have to add more RAM? Currently there is only one disk I am using for caching. Will it help if I increase the number of raw disks for caching? Regards, Randeep On Wed, Jul 13, 2016 at 4:30 AM, James Peach <jpe...@apache.org> wrote: > > > On Jul 12, 2016, at 6:05 AM, Randeep <randeep...@gmail.com> wrote: > > > > Hi all, > > > > I'm trying to understand what is causing the load on the ats server. Not > sure whether is RAM or disk or CPU is giving the issues. > > From the output you posted it seems pretty likely that you are IO bound on > reads. You should investigate why that is happening. For most caching > workloads, I would expect the RAM cache to give a good hit rate, so that is > one avenue of investigation. > > > on top output I can see a lot of iowait. > > > > top - 18:12:00 up 4:32, 3 users, load average: 8.15, 8.20, 8.53 > > Tasks: 234 total, 2 running, 232 sleeping, 0 stopped, 0 zombie > > Cpu(s): 7.2%us, 10.7%sy, 0.0%ni, 34.0%id, 46.5%wa, 0.0%hi, 1.7%si, > 0.0%st > > Mem: 7848208k total, 7701228k used, 146980k free, 20008k buffers > > Swap: 8388604k total, 426796k used, 7961808k free, 250532k cached > > > > PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND > > 14138 ats 20 0 8199m 6.7g 4852 S 9.0 89.8 7:23.41 > /opt/ats/bin/traffic_server -M --bind_stdout > /opt/ats/var/log/trafficserver/traffic.out --bind_stderr /opt/ > > > > And on iostat, > > Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s > avgrq-sz avgqu-sz await svctm %util > > sda 0.00 83.00 257.00 54.00 134672.00 21248.00 > 501.35 10.51 33.69 3.22 100.00 > > > > on iotop: > > Total DISK READ: 50.46 M/s | Total DISK WRITE: 14.35 M/s > > TID PRIO USER DISK READ DISK WRITE SWAPIN IO> COMMAND > > 14154 be/4 ats 3.33 M/s 0.00 B/s 0.00 % 91.45 % > traffic_server -M --bind_stdout > /opt/ats/var/log/traf~s/var/log/trafficserver/traffic.out --httpport 80:fd=9 > > 14156 be/4 ats 7.28 M/s 2025.05 K/s 0.00 % 90.56 % > traffic_server -M --bind_stdout > /opt/ats/var/log/traf~s/var/log/trafficserver/traffic.out --httpport 80:fd=9 > > 14157 be/4 ats 6.88 M/s 0.00 B/s 0.00 % 90.52 % > traffic_server -M --bind_stdout > /opt/ats/var/log/traf~s/var/log/trafficserver/traffic.out --httpport 80:fd=9 > > 14155 be/4 ats 2.53 M/s 3.32 M/s 0.00 % 82.89 % > traffic_server -M --bind_stdout > /opt/ats/var/log/traf~s/var/log/trafficserver/traffic.out --httpport 80:fd=9 > > 14158 be/4 ats 9.58 M/s 3.33 M/s 0.00 % 75.91 % > traffic_server -M --bind_stdout > /opt/ats/var/log/traf~s/var/log/trafficserver/traffic.out --httpport 80:fd=9 > > 14161 be/4 ats 7.67 M/s 0.00 B/s 0.00 % 73.36 % > traffic_server -M --bind_stdout > /opt/ats/var/log/traf~s/var/log/trafficserver/traffic.out --httpport 80:fd=9 > > 14159 be/4 ats 5.89 M/s 2025.05 K/s 0.00 % 73.27 % > traffic_server -M --bind_stdout > /opt/ats/var/log/traf~s/var/log/trafficserver/traffic.out --httpport 80:fd=9 > > 14160 be/4 ats 7.30 M/s 3.75 M/s 0.00 % 66.01 % > traffic_server -M --bind_stdout > /opt/ats/var/log/traf~s/var/log/trafficserver/traffic.out --httpport 80:fd=9 > > > > But I have disabled all the logs. I don't know why it still shows. On > production, usually everyone disables the logs? > > > > [root@main ~]# free -m > > total used free shared buffers cached > > Mem: 7664 7488 175 0 13 210 > > -/+ buffers/cache: 7265 398 > > Swap: 8191 416 7775 > > [root@main ~]# w > > 18:15:25 up 4:35, 3 users, load average: 8.07, 8.14, 8.43 > > > > I am using ats to cache live channels. Currently I have enabled 45 > channels. We have to enable 400 channels. So I am checking what resources I > have to add. > > > > Any suggestions will be appreciated > > > > Best Regards, > > -- > > Randeep > > Mob: +919447831699[kerala] > > Mob: +919880050349[B'lore] > > http://twitter.com/Randeeppr > > http://in.linkedin.com/in/randeeppr > > > > > > > > Randeep Raman > > about.me/Randeeppr > > > > > > -- Randeep Mob: +919447831699[kerala] Mob: +919880050349[B'lore] http://twitter.com/Randeeppr http://in.linkedin.com/in/randeeppr [image: --] Randeep Raman [image: http://]about.me/Randeeppr <http://about.me/Randeeppr>
