可读的jvm gc日志时间

1. jdk 6u4之后可用-XX:+PrintGCDateStamps参数

2.python转换脚本

#!/usr/bin/env python
 
import sys, os, datetime
 
# true if string is a positive float
def validSeconds(str_sec):
    try:
        return 0 < float(str_sec)
    except ValueError:
        return False
 
# show usage                
if len(sys.argv) < 2:
    print "Usage: %s <gc.log>" % (sys.argv[0])
    sys.exit(1)
 
file_str = sys.argv[1]
lastmod_date = datetime.datetime.fromtimestamp(os.path.getmtime(file_str))
 
file = open(file_str, 'r')
lines = file.readlines()
file.close()
 
# get last elapsed time
for line in reversed(lines):
    parts = line.split(':')
    if validSeconds(parts[0]):
        break
 
# calculate start time
start_date = lastmod_date - datetime.timedelta(seconds=float(parts[0]))
 
# print file prepending human readable time where appropiate  
for line in lines:
    parts = line.split(':')
    if not validSeconds(parts[0]):
        print line.rstrip()
        continue
    line_date = start_date + datetime.timedelta(seconds=float(parts[0]))
    print "%s: %s" % (line_date.isoformat(), line.rstrip())