数据库的大日志文件处理技巧

[root@yeyz ~]# split --help
Usage: split [OPTION]... [INPUT [PREFIX]]
Output fixed-size pieces of INPUT to PREFIXaa, PREFIXab, ...; default
size is 1000 lines, and default PREFIX is 'x'.  With no INPUT, or when INPUT
is -, read standard input.

Mandatory arguments to long options are mandatory for short options too.
  -a, --suffix-length=N   generate suffixes of length N (default 2)
      --additional-suffix=SUFFIX  append an additional SUFFIX to file names
  -b, --bytes=SIZE        put SIZE bytes per output file
  -C, --line-bytes=SIZE   put at most SIZE bytes of lines per output file
  -d, --numeric-suffixes[=FROM]  use numeric suffixes instead of alphabetic;
                                   FROM changes the start value (default 0)
  -e, --elide-empty-files  do not generate empty output files with '-n'
      --filter=COMMAND    write to shell COMMAND; file name is $FILE
  -l, --lines=NUMBER      put NUMBER lines per output file
  -n, --number=CHUNKS     generate CHUNKS output files; see explanation below
  -u, --unbuffered        immediately copy input to output with '-n r/...'
      --verbose           print a diagnostic just before each
                            output file is opened
      --help     display this help and exit
      --version  output version information and exit

SIZE is an integer and optional unit (example: 10M is 10*1024*1024).  Units
are K, M, G, T, P, E, Z, Y (powers of 1024) or KB, MB, ... (powers of 1000).

CHUNKS may be:
N       split into N files based on size of input
K/N     output Kth of N to stdout
l/N     split into N files without splitting lines
l/K/N   output Kth of N to stdout without splitting lines
r/N     like 'l' but use round robin distribution
r/K/N   likewise but only output Kth of N to stdout

GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
For complete documentation, run: info coreutils 'split invocation'

[root@yeyz test]# ll
total 31524
-rw-r--r-- 1 root root 32277286 May 12 23:52 b.txt
[root@yeyz test]# split -b 1M b.txt
[root@yeyz test]# ll
total 63048
-rw-r--r-- 1 root root 32277286 May 12 23:52 b.txt
-rw-r--r-- 1 root root  1048576 May 12 23:52 xaa
-rw-r--r-- 1 root root  1048576 May 12 23:52 xab
-rw-r--r-- 1 root root  1048576 May 12 23:52 xac
-rw-r--r-- 1 root root  1048576 May 12 23:52 xad
-rw-r--r-- 1 root root  1048576 May 12 23:52 xae
-rw-r--r-- 1 root root  1048576 May 12 23:52 xaf
-rw-r--r-- 1 root root  1048576 May 12 23:52 xag
-rw-r--r-- 1 root root  1048576 May 12 23:52 xah
-rw-r--r-- 1 root root  1048576 May 12 23:52 xai
-rw-r--r-- 1 root root  1048576 May 12 23:52 xaj
-rw-r--r-- 1 root root  1048576 May 12 23:52 xak
-rw-r--r-- 1 root root  1048576 May 12 23:52 xal
-rw-r--r-- 1 root root  1048576 May 12 23:52 xam
-rw-r--r-- 1 root root  1048576 May 12 23:52 xan
-rw-r--r-- 1 root root  1048576 May 12 23:52 xao
-rw-r--r-- 1 root root  1048576 May 12 23:52 xap

/data1/mongo[0-9]*[0-9]/log/mongod.log {
    minsize 1k
    daily
    dateext
    rotate 10
    maxage 10
    start 0
    missingok
    create 0644 root root
    notifempty
    sharedscripts
    postrotate
        for port in $(ps axu | grep mongo[0-9]*.conf | awk -F '/' '{print $(NF-1)}' | sed 's/mongo//g')
        do
                /bin/rm -f /data1/mongo${port}/log/mongod.log.????-??-??T??-??-?? 2> /dev/null
                /bin/sleep 1
                /bin/kill -SIGUSR1 $(cat /data1/mongo${port}/mongod.pid  2> /dev/null) 2> /dev/null
                /bin/rm -f /data1/mongo${port}/log/mongod.log.????-??-??T??-??-?? 2> /dev/null
        done
    endscript
}