Monday, October 6, 2014

InfluxDB on Ubuntu: Too many open files

I had InfluxDB (a great time-series datastore) running on Ubuntu, and kept running into these errors:

IO error: /opt/influxdb/shared/data/db/shard_db_v2/00031/356947.ldb: Too many open files

The issue was that the Ubuntu default for open files is 1024:

root@server:~# ulimit -Sn
1024

There were two steps required to fix this issue with InfluxDB.

  • Set the open file limit system wide
    • Edit /etc/security/limits.conf and add the following:
    • * soft nofile 100000
    • * hard nofile 100000
This raised the limits, but when the InfluxDB process started, it was still getting the old limits:


iclark@gar-network-datastore:~$ cat /proc/992/limits
Limit                     Soft Limit           Hard Limit           Units
Max cpu time              unlimited            unlimited            seconds
Max file size             unlimited            unlimited            bytes
Max data size             unlimited            unlimited            bytes
Max stack size            8388608              unlimited            bytes
Max core file size        0                    unlimited            bytes
Max resident set          unlimited            unlimited            bytes
Max processes             47573                47573                processes
Max open files            1024                 4096                 files
Max locked memory         65536                65536                bytes
Max address space         unlimited            unlimited            bytes
Max file locks            unlimited            unlimited            locks
Max pending signals       47573                47573                signals
Max msgqueue size         819200               819200               bytes
Max nice priority         0                    0
Max realtime priority     0                    0
Max realtime timeout      unlimited            unlimited            us

  • To fix this, I had to set the ulimit value in the influxdb init script
    • Edit /etc/init.d/influxdb and add the following to the beginning of the script:
    • ulimit -n 100000
After this value was added, I just stopped and started the InfluxDB process, and voila:

root@gar-network-datastore:~# cat /proc/1279/limits
Limit                     Soft Limit           Hard Limit           Units
Max cpu time              unlimited            unlimited            seconds
Max file size             unlimited            unlimited            bytes
Max data size             unlimited            unlimited            bytes
Max stack size            8388608              unlimited            bytes
Max core file size        0                    unlimited            bytes
Max resident set          unlimited            unlimited            bytes
Max processes             47573                47573                processes
Max open files            100000               100000               files
Max locked memory         65536                65536                bytes
Max address space         unlimited            unlimited            bytes
Max file locks            unlimited            unlimited            locks
Max pending signals       47573                47573                signals
Max msgqueue size         819200               819200               bytes
Max nice priority         0                    0
Max realtime priority     0                    0
Max realtime timeout      unlimited            unlimited            us