On 12/02/2015 03:24 PM, Dave Young wrote: > Hi, > > On 12/02/15 at 01:29pm, "Zhou, Wenjian/???" wrote: >> I think there is no problem if other test results are as expected. >> >> --num-threads mainly reduces the time of compressing. >> So for lzo, it can't do much help at most of time. > > Seems the help of --num-threads does not say it exactly: > > [--num-threads THREADNUM]: > Using multiple threads to read and compress data of each page in parallel. > And it will reduces time for saving DUMPFILE. > This feature only supports creating DUMPFILE in kdump-comressed format from > VMCORE in kdump-compressed format or elf format. > > Lzo is also a compress method, it should be mentioned that --num-threads only > supports zlib compressed vmcore. > Sorry, it seems that something I said is not so clear. lzo is also supported. Since lzo compresses data at a high speed, the improving of the performance is not so obvious at most of time. > Also worth to mention about the recommended -d value for this feature. > Yes, I think it's worth. I forgot it. -- Thanks Zhou