sa弄长些，弄频繁些

默认是是10分钟一采集
cat /etc/cron.d/sysstat
*/10 * * * * root /usr/lib64/sa/sa1 1 1
把10修改为1，就变成一分钟了。

默认是保留7天，
cat /etc/sysconfig/sysstat
# How long to keep log files (in days).
# If value is greater than 28, then log files are kept in
# multiple directories, one for each month.
HISTORY=7
把7修改为27就可以