今天報警一條error：host xxxx has more lowmem_prunes,please add Memory...
這個報警是一個shell腳本寫的
Qcache_lowmem_prunes=`$Procedure_source -h$host -P$Port -uadmin -pxxxx -e"show status" | grep "Qcache_lowmem_prunes" | awk '{print $2}'`
if [ $Qcache_lowmem_prunes -gt 700000000 ]
then
echo "$host has more lowmem_prunes,please add Memory" | mail -s "$host has more lowmem_prunes,now lowmem_prunes is $Qcache_lowmem_prunes `date +"%R %F"`" $maillist
else
echo "$host lowmem_prunes ok"
fi官方文檔對 Qcache_lowmem_prunes的解釋：
The number of queries that were deleted from the query cache because of low memory.
大概意思是cache池滿了，所以導致的query修剪。
結合下面兩篇文章，做了如下決定：改my.cnf文件，query_cache_type=1->0 query_cache_size=1G->0
務必重啓
參考：http://t.cn/RAF4d7z http://t.cn/RAF4d7Z