Hi , Understand now. One more question, what backlog for? Why read only with verify do not need it? Thanks! On Thu, Sep 15, 2011 at 1:39 AM, Jens Axboe <axboe@xxxxxxxxx> wrote: > On 2011-09-14 11:53, Zhang Taile wrote: >> HI >> When I do RandWrite with verify, fio will use a lot of memory. The fio >> will increase memory about 10MB in every second. And, the system will >> become very slow, after fio start to use swap partition. >> >> For example, if use fio with following configuration, >> [rand-write] >> rw=randwrite >> numjobs=32 >> loops=10 >> thread=1 >> filename=/dev/sdb >> verify=md5 >> verify_interval=4k >> >> after minutes, top will Like this : >> PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND >> 3749 root 15 0 2672m 1.5g 304m S 169.4 40.4 4:10.04 fio >> >> >> If remove the verify from the configuration, there will be no the >> memory problem. >> >> I guess it is a memory leak problem? > > It's probably not a leak, fio will use a lot of memory for your job > file. Each job will maintain a full backlog of meta data for blocks > written, so it can safely verify it. And you have 32 jobs, so it'll be a > lot of memory. > > -- > Jens Axboe > > -- Zhang, Taile 张泰乐 zhangtl@xxxxxxxxx MP:18611745290 msn:zhangtaile@xxxxxxxxxxx skype: zhangtaile -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
