background

we would set env var USE_SSE=1 when compiling Rocksdb, OTHERWISE it would always failed at linking stage where encountering errors of lack of some instructions such as: no such instruction: shlx %rdx,%rax,%rax'`. but what the fuck is USE_SSE ?

日常cheatsheet～

• run valgrind for a program

valgrind --tool=memcheck --leak-check=full --log-file=leak.log --soname-synonyms=somalloc=NONE <some_exe> [<some_exe_args>]

• run tcpdump to capture mysql queries:

tcpdump -r /tmp/a.cap -A -S -n -nn  | grep -i -E "select|insert|update|delete|replace" | sed 's%\(.*\)\([.]\{4\}\)\(.*\)%\3%' | less

• python scripts:

python -m SimpleHTTPServer 8123
wget -c -r -nH -m --limit-rate=400m "http://ip:8123/xxxx"

python -c 'from zlib import crc32; print crc32("1476777") % 1024'

#!/usr/bin/python
# -*- coding: UTF-8 -*-
import sys
import json
data = ""
for line in sys.stdin:
        data += line
text = json.loads(data)
print(text)

• tee with a pipe output to screen and a file

echo "hello" | tee abc.txt

• ps

• top

• tasr

• sar