Re: read performance is too low compared to write - /dev/sda1
On 14 November 2014 19:22, Roger Heflin wrote: > What kind of underlying disk is it? GEN3 Sata link, SSD from Samsung. > > On Fri, Nov 14, 2014 at 7:36 AM, Jagan Teki wrote: >> On 14 November 2014 18:50, Roger Heflin wrote: >>> If you are robocoping small files you will hit other limits. >>> >>> Best I have seen with small files is around 30 files/second, and that >>> involves multiple copies going on. Remember with a small files there >>> are several reads and writes that need to be done to complete a create >>> of a small file and each of these take time.30 files/second ~ 30ms >>> per file, not that bad considering that on a real spinning disk a >>> single read/write op is 5-10ms, and creating the file entry, copying >>> data and closing the file takes several operations (at least create >>> file entry, write small amount of data, update file entry >>> date/time/info). If the write in the middle is not a significant >>> amount of data, the 2 extra ops are what hurts. >>> >> >> But, I tried 4gb and 1gb files both got a similar numbers. >> >>> On Fri, Nov 14, 2014 at 6:55 AM, Jagan Teki >>> wrote: Hi, I'm doing a performance testing on my bench ARM box. 1. dd test: I have validate the read and write by mounting /dev/sda1 with ext4 filesystem, able to get the good performance numbers where read is high compared to write 2. robocopy test: - mkfs.ext4 /dev/sda1 - mount /dev/sda1 /media/disk - << configured samba >> - Mapped the /media/disk on windows - login on the mapped driver in windows - did a robocopy test, where write got 84MBps and read 14MBps read performance is too slow when compared to write in robocopy case. Can anyone help me out, how to debug this further. >> >> thanks! >> -- >> Jagan. -- Jagan. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: read performance is too low compared to write - /dev/sda1
On 14 November 2014 19:22, Roger Heflin rogerhef...@gmail.com wrote: What kind of underlying disk is it? GEN3 Sata link, SSD from Samsung. On Fri, Nov 14, 2014 at 7:36 AM, Jagan Teki jagannadh.t...@gmail.com wrote: On 14 November 2014 18:50, Roger Heflin rogerhef...@gmail.com wrote: If you are robocoping small files you will hit other limits. Best I have seen with small files is around 30 files/second, and that involves multiple copies going on. Remember with a small files there are several reads and writes that need to be done to complete a create of a small file and each of these take time.30 files/second ~ 30ms per file, not that bad considering that on a real spinning disk a single read/write op is 5-10ms, and creating the file entry, copying data and closing the file takes several operations (at least create file entry, write small amount of data, update file entry date/time/info). If the write in the middle is not a significant amount of data, the 2 extra ops are what hurts. But, I tried 4gb and 1gb files both got a similar numbers. On Fri, Nov 14, 2014 at 6:55 AM, Jagan Teki jagannadh.t...@gmail.com wrote: Hi, I'm doing a performance testing on my bench ARM box. 1. dd test: I have validate the read and write by mounting /dev/sda1 with ext4 filesystem, able to get the good performance numbers where read is high compared to write 2. robocopy test: - mkfs.ext4 /dev/sda1 - mount /dev/sda1 /media/disk - configured samba - Mapped the /media/disk on windows - login on the mapped driver in windows - did a robocopy test, where write got 84MBps and read 14MBps read performance is too slow when compared to write in robocopy case. Can anyone help me out, how to debug this further. thanks! -- Jagan. -- Jagan. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: read performance is too low compared to write - /dev/sda1
What kind of underlying disk is it? On Fri, Nov 14, 2014 at 7:36 AM, Jagan Teki wrote: > On 14 November 2014 18:50, Roger Heflin wrote: >> If you are robocoping small files you will hit other limits. >> >> Best I have seen with small files is around 30 files/second, and that >> involves multiple copies going on. Remember with a small files there >> are several reads and writes that need to be done to complete a create >> of a small file and each of these take time.30 files/second ~ 30ms >> per file, not that bad considering that on a real spinning disk a >> single read/write op is 5-10ms, and creating the file entry, copying >> data and closing the file takes several operations (at least create >> file entry, write small amount of data, update file entry >> date/time/info). If the write in the middle is not a significant >> amount of data, the 2 extra ops are what hurts. >> > > But, I tried 4gb and 1gb files both got a similar numbers. > >> On Fri, Nov 14, 2014 at 6:55 AM, Jagan Teki wrote: >>> Hi, >>> >>> I'm doing a performance testing on my bench ARM box. >>> >>> 1. dd test: I have validate the read and write by mounting /dev/sda1 >>> with ext4 filesystem, >>> able to get the good performance numbers where read is high >>> compared to write >>> >>> 2. robocopy test: >>> - mkfs.ext4 /dev/sda1 >>> - mount /dev/sda1 /media/disk >>> - << configured samba >> >>> - Mapped the /media/disk on windows >>> - login on the mapped driver in windows >>> - did a robocopy test, where write got 84MBps and read 14MBps >>> >>> read performance is too slow when compared to write in robocopy case. >>> Can anyone help me out, how to debug this further. > > thanks! > -- > Jagan. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: read performance is too low compared to write - /dev/sda1
On 14 November 2014 18:50, Roger Heflin wrote: > If you are robocoping small files you will hit other limits. > > Best I have seen with small files is around 30 files/second, and that > involves multiple copies going on. Remember with a small files there > are several reads and writes that need to be done to complete a create > of a small file and each of these take time.30 files/second ~ 30ms > per file, not that bad considering that on a real spinning disk a > single read/write op is 5-10ms, and creating the file entry, copying > data and closing the file takes several operations (at least create > file entry, write small amount of data, update file entry > date/time/info). If the write in the middle is not a significant > amount of data, the 2 extra ops are what hurts. > But, I tried 4gb and 1gb files both got a similar numbers. > On Fri, Nov 14, 2014 at 6:55 AM, Jagan Teki wrote: >> Hi, >> >> I'm doing a performance testing on my bench ARM box. >> >> 1. dd test: I have validate the read and write by mounting /dev/sda1 >> with ext4 filesystem, >> able to get the good performance numbers where read is high >> compared to write >> >> 2. robocopy test: >> - mkfs.ext4 /dev/sda1 >> - mount /dev/sda1 /media/disk >> - << configured samba >> >> - Mapped the /media/disk on windows >> - login on the mapped driver in windows >> - did a robocopy test, where write got 84MBps and read 14MBps >> >> read performance is too slow when compared to write in robocopy case. >> Can anyone help me out, how to debug this further. thanks! -- Jagan. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: read performance is too low compared to write - /dev/sda1
If you are robocoping small files you will hit other limits. Best I have seen with small files is around 30 files/second, and that involves multiple copies going on. Remember with a small files there are several reads and writes that need to be done to complete a create of a small file and each of these take time.30 files/second ~ 30ms per file, not that bad considering that on a real spinning disk a single read/write op is 5-10ms, and creating the file entry, copying data and closing the file takes several operations (at least create file entry, write small amount of data, update file entry date/time/info). If the write in the middle is not a significant amount of data, the 2 extra ops are what hurts. On Fri, Nov 14, 2014 at 6:55 AM, Jagan Teki wrote: > Hi, > > I'm doing a performance testing on my bench ARM box. > > 1. dd test: I have validate the read and write by mounting /dev/sda1 > with ext4 filesystem, > able to get the good performance numbers where read is high > compared to write > > 2. robocopy test: > - mkfs.ext4 /dev/sda1 > - mount /dev/sda1 /media/disk > - << configured samba >> > - Mapped the /media/disk on windows > - login on the mapped driver in windows > - did a robocopy test, where write got 84MBps and read 14MBps > > read performance is too slow when compared to write in robocopy case. > Can anyone help me out, how to debug this further. > > thanks! > -- > Jagan. > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
read performance is too low compared to write - /dev/sda1
Hi, I'm doing a performance testing on my bench ARM box. 1. dd test: I have validate the read and write by mounting /dev/sda1 with ext4 filesystem, able to get the good performance numbers where read is high compared to write 2. robocopy test: - mkfs.ext4 /dev/sda1 - mount /dev/sda1 /media/disk - << configured samba >> - Mapped the /media/disk on windows - login on the mapped driver in windows - did a robocopy test, where write got 84MBps and read 14MBps read performance is too slow when compared to write in robocopy case. Can anyone help me out, how to debug this further. thanks! -- Jagan. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
read performance is too low compared to write - /dev/sda1
Hi, I'm doing a performance testing on my bench ARM box. 1. dd test: I have validate the read and write by mounting /dev/sda1 with ext4 filesystem, able to get the good performance numbers where read is high compared to write 2. robocopy test: - mkfs.ext4 /dev/sda1 - mount /dev/sda1 /media/disk - configured samba - Mapped the /media/disk on windows - login on the mapped driver in windows - did a robocopy test, where write got 84MBps and read 14MBps read performance is too slow when compared to write in robocopy case. Can anyone help me out, how to debug this further. thanks! -- Jagan. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: read performance is too low compared to write - /dev/sda1
If you are robocoping small files you will hit other limits. Best I have seen with small files is around 30 files/second, and that involves multiple copies going on. Remember with a small files there are several reads and writes that need to be done to complete a create of a small file and each of these take time.30 files/second ~ 30ms per file, not that bad considering that on a real spinning disk a single read/write op is 5-10ms, and creating the file entry, copying data and closing the file takes several operations (at least create file entry, write small amount of data, update file entry date/time/info). If the write in the middle is not a significant amount of data, the 2 extra ops are what hurts. On Fri, Nov 14, 2014 at 6:55 AM, Jagan Teki jagannadh.t...@gmail.com wrote: Hi, I'm doing a performance testing on my bench ARM box. 1. dd test: I have validate the read and write by mounting /dev/sda1 with ext4 filesystem, able to get the good performance numbers where read is high compared to write 2. robocopy test: - mkfs.ext4 /dev/sda1 - mount /dev/sda1 /media/disk - configured samba - Mapped the /media/disk on windows - login on the mapped driver in windows - did a robocopy test, where write got 84MBps and read 14MBps read performance is too slow when compared to write in robocopy case. Can anyone help me out, how to debug this further. thanks! -- Jagan. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: read performance is too low compared to write - /dev/sda1
On 14 November 2014 18:50, Roger Heflin rogerhef...@gmail.com wrote: If you are robocoping small files you will hit other limits. Best I have seen with small files is around 30 files/second, and that involves multiple copies going on. Remember with a small files there are several reads and writes that need to be done to complete a create of a small file and each of these take time.30 files/second ~ 30ms per file, not that bad considering that on a real spinning disk a single read/write op is 5-10ms, and creating the file entry, copying data and closing the file takes several operations (at least create file entry, write small amount of data, update file entry date/time/info). If the write in the middle is not a significant amount of data, the 2 extra ops are what hurts. But, I tried 4gb and 1gb files both got a similar numbers. On Fri, Nov 14, 2014 at 6:55 AM, Jagan Teki jagannadh.t...@gmail.com wrote: Hi, I'm doing a performance testing on my bench ARM box. 1. dd test: I have validate the read and write by mounting /dev/sda1 with ext4 filesystem, able to get the good performance numbers where read is high compared to write 2. robocopy test: - mkfs.ext4 /dev/sda1 - mount /dev/sda1 /media/disk - configured samba - Mapped the /media/disk on windows - login on the mapped driver in windows - did a robocopy test, where write got 84MBps and read 14MBps read performance is too slow when compared to write in robocopy case. Can anyone help me out, how to debug this further. thanks! -- Jagan. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: read performance is too low compared to write - /dev/sda1
What kind of underlying disk is it? On Fri, Nov 14, 2014 at 7:36 AM, Jagan Teki jagannadh.t...@gmail.com wrote: On 14 November 2014 18:50, Roger Heflin rogerhef...@gmail.com wrote: If you are robocoping small files you will hit other limits. Best I have seen with small files is around 30 files/second, and that involves multiple copies going on. Remember with a small files there are several reads and writes that need to be done to complete a create of a small file and each of these take time.30 files/second ~ 30ms per file, not that bad considering that on a real spinning disk a single read/write op is 5-10ms, and creating the file entry, copying data and closing the file takes several operations (at least create file entry, write small amount of data, update file entry date/time/info). If the write in the middle is not a significant amount of data, the 2 extra ops are what hurts. But, I tried 4gb and 1gb files both got a similar numbers. On Fri, Nov 14, 2014 at 6:55 AM, Jagan Teki jagannadh.t...@gmail.com wrote: Hi, I'm doing a performance testing on my bench ARM box. 1. dd test: I have validate the read and write by mounting /dev/sda1 with ext4 filesystem, able to get the good performance numbers where read is high compared to write 2. robocopy test: - mkfs.ext4 /dev/sda1 - mount /dev/sda1 /media/disk - configured samba - Mapped the /media/disk on windows - login on the mapped driver in windows - did a robocopy test, where write got 84MBps and read 14MBps read performance is too slow when compared to write in robocopy case. Can anyone help me out, how to debug this further. thanks! -- Jagan. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
