Hi all, I want to make a btrfs raid0 on 2 partitions of my pc. Until now I am using the mdadm tools to make a software raid of the 2 partitions /dev/sde2, /dev/sdd2 and then mkfs.etx4 the newly created /dev/md0 device. From performance point of view is it better to keep the configuration of mdadm and just format the /dev/md0 device as btrfs OR delete the raid device and format the 2 partitions /dev/sde2 /dev/sdd2 as a btrfs with 2 devices? mkfs.btrfs /dev/sde2 /dev/sdd2 On a sidenote: If I decide to go for raid5 which is not supported currently from mkfs I have to use the mdadm tool anyway, right? -- Caution: breathing may be hazardous to your health. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thursday 05 August 2010 16:15:22 Leonidas Spyropoulos wrote:> Hi all, > > I want to make a btrfs raid0 on 2 partitions of my pc. > Until now I am using the mdadm tools to make a software raid of the 2 > partitions /dev/sde2, /dev/sdd2 > and then mkfs.etx4 the newly created /dev/md0 device. > From performance point of view is it better to keep the configuration of > mdadm and just format the /dev/md0 device as btrfs OR > delete the raid device and format the 2 partitions /dev/sde2 /dev/sdd2 > as a btrfs with 2 devices? > mkfs.btrfs /dev/sde2 /dev/sdd2Btrfs already supports metadata mirroring when the data is striped. What this means, is while the performance should be more-or-less identical to MD RAID0 (if it isn''t it''s a bug), your data is a bit more secure as the metadata describing it resides on both drives. Later on it will be possible to selct which directories/files should have what level of redundancy. This will allow to have ~/work RAID1-ed and ~/videos RAID0-ed while keeping both directories on the same partition and filesystem.> On a sidenote: > If I decide to go for raid5 which is not supported currently from mkfs > I have to use the mdadm tool anyway, right?yes, RAID5 code is not in trunk yet. -- Hubert Kario QBS - Quality Business Software 02-656 Warszawa, ul. Ksawerów 30/85 tel. +48 (22) 646-61-51, 646-74-24 www.qbs.com.pl -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Do I have to change the partition ID flag of each partition? Currently is set to fd (Linux Raid autodetect) for used from mdadm mkfs.btrfs supports that or needs to be 83 (Linux) ? On Thu, Aug 5, 2010 at 3:40 PM, Hubert Kario <hka@qbs.com.pl> wrote:> On Thursday 05 August 2010 16:15:22 Leonidas Spyropoulos wrote: >> Hi all, >> >> I want to make a btrfs raid0 on 2 partitions of my pc. >> Until now I am using the mdadm tools to make a software raid of the 2 >> partitions /dev/sde2, /dev/sdd2 >> and then mkfs.etx4 the newly created /dev/md0 device. >> From performance point of view is it better to keep the configuration of >> mdadm and just format the /dev/md0 device as btrfs OR >> delete the raid device and format the 2 partitions /dev/sde2 /dev/sdd2 >> as a btrfs with 2 devices? >> mkfs.btrfs /dev/sde2 /dev/sdd2 > > Btrfs already supports metadata mirroring when the data is striped. What this > means, is while the performance should be more-or-less identical to MD RAID0 > (if it isn''t it''s a bug), your data is a bit more secure as the metadata > describing it resides on both drives. Later on it will be possible to selct > which directories/files should have what level of redundancy. This will allow > to have ~/work RAID1-ed and ~/videos RAID0-ed while keeping both directories > on the same partition and filesystem. > >> On a sidenote: >> If I decide to go for raid5 which is not supported currently from mkfs >> I have to use the mdadm tool anyway, right? > > yes, RAID5 code is not in trunk yet. > > -- > Hubert Kario > QBS - Quality Business Software > 02-656 Warszawa, ul. Ksawerów 30/85 > tel. +48 (22) 646-61-51, 646-74-24 > www.qbs.com.pl >-- Caution: breathing may be hazardous to your health. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 6 August 2010 20:23, Leonidas Spyropoulos <artafinde@gmail.com> wrote:> Do I have to change the partition ID flag of each partition? > Currently is set to fd (Linux Raid autodetect) for used from mdadm > mkfs.btrfs supports that or needs to be 83 (Linux) ?FD is for mdraid integrated into the Linux kernel. I have mine at 83. It won''t hurt to have them at FD, but the kernel will spend extra time as it probes the devices on boot, causing a slight slowdown.> > On Thu, Aug 5, 2010 at 3:40 PM, Hubert Kario <hka@qbs.com.pl> wrote: >> On Thursday 05 August 2010 16:15:22 Leonidas Spyropoulos wrote: >>> Hi all, >>> >>> I want to make a btrfs raid0 on 2 partitions of my pc. >>> Until now I am using the mdadm tools to make a software raid of the 2 >>> partitions /dev/sde2, /dev/sdd2 >>> and then mkfs.etx4 the newly created /dev/md0 device. >>> From performance point of view is it better to keep the configuration of >>> mdadm and just format the /dev/md0 device as btrfs OR >>> delete the raid device and format the 2 partitions /dev/sde2 /dev/sdd2 >>> as a btrfs with 2 devices? >>> mkfs.btrfs /dev/sde2 /dev/sdd2 >> >> Btrfs already supports metadata mirroring when the data is striped. What this >> means, is while the performance should be more-or-less identical to MD RAID0 >> (if it isn''t it''s a bug), your data is a bit more secure as the metadata >> describing it resides on both drives. Later on it will be possible to selct >> which directories/files should have what level of redundancy. This will allow >> to have ~/work RAID1-ed and ~/videos RAID0-ed while keeping both directories >> on the same partition and filesystem. >> >>> On a sidenote: >>> If I decide to go for raid5 which is not supported currently from mkfs >>> I have to use the mdadm tool anyway, right? >> >> yes, RAID5 code is not in trunk yet. >> >> -- >> Hubert Kario >> QBS - Quality Business Software >> 02-656 Warszawa, ul. Ksawerów 30/85 >> tel. +48 (22) 646-61-51, 646-74-24 >> www.qbs.com.pl >> > > > > -- > Caution: breathing may be hazardous to your health. > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >Regards, Sebastian J. PS. Please try to bottom-post rather than top-post. Here''s a link I can advise reading for a clarification on why bottom posting is essential: http://www.caliburn.nl/topposting.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Aug 6, 2010 at 7:32 PM, Sebastian ''gonX'' Jensen <gonx@overclocked.net> wrote:> On 6 August 2010 20:23, Leonidas Spyropoulos <artafinde@gmail.com> wrote: >> Do I have to change the partition ID flag of each partition? >> Currently is set to fd (Linux Raid autodetect) for used from mdadm >> mkfs.btrfs supports that or needs to be 83 (Linux) ? > > FD is for mdraid integrated into the Linux kernel. I have mine at 83. > It won''t hurt to have them at FD, but the kernel will spend extra time > as it probes the devices on boot, causing a slight slowdown.Ok done them id 83 and used 3 devices eventually Using raid0 for data and metadata # mkfs.btrfs -m raid0 -d raid0 /dev/sdc1 /dev/sdd2 /dev/sde2 2 SATA and 1 ATA drive I thought that ATA will bottleneck the other 2 drives but seems like I gain something from it. Using iozone for benchmark: # iozone -s 8g -r 1024 -i 0 -i 1 with 2 SATA devices and then 3 devices (SATA + ATA): KB reclen write rewrite read reread 8388608 1024 134869 139607 229146 228800 8388608 1024 135151 139050 233461 235929 The above is with -o compress option enabled and my cpu topped up on 100% cpu (both cores) while test and copy huge data. Is it possible I am bottlenecked by my cpu speed? AMD Opteron 165 @ 2700 Mhz>> >> On Thu, Aug 5, 2010 at 3:40 PM, Hubert Kario <hka@qbs.com.pl> wrote: >>> On Thursday 05 August 2010 16:15:22 Leonidas Spyropoulos wrote: >>>> Hi all, >>>> >>>> I want to make a btrfs raid0 on 2 partitions of my pc. >>>> Until now I am using the mdadm tools to make a software raid of the 2 >>>> partitions /dev/sde2, /dev/sdd2 >>>> and then mkfs.etx4 the newly created /dev/md0 device. >>>> From performance point of view is it better to keep the configuration of >>>> mdadm and just format the /dev/md0 device as btrfs OR >>>> delete the raid device and format the 2 partitions /dev/sde2 /dev/sdd2 >>>> as a btrfs with 2 devices? >>>> mkfs.btrfs /dev/sde2 /dev/sdd2 >>> >>> Btrfs already supports metadata mirroring when the data is striped. What this >>> means, is while the performance should be more-or-less identical to MD RAID0 >>> (if it isn''t it''s a bug), your data is a bit more secure as the metadata >>> describing it resides on both drives. Later on it will be possible to selct >>> which directories/files should have what level of redundancy. This will allow >>> to have ~/work RAID1-ed and ~/videos RAID0-ed while keeping both directories >>> on the same partition and filesystem. >>> >>>> On a sidenote: >>>> If I decide to go for raid5 which is not supported currently from mkfs >>>> I have to use the mdadm tool anyway, right? >>> >>> yes, RAID5 code is not in trunk yet. >>> >>> -- >>> Hubert Kario >>> QBS - Quality Business Software >>> 02-656 Warszawa, ul. Ksawerów 30/85 >>> tel. +48 (22) 646-61-51, 646-74-24 >>> www.qbs.com.pl >>> >> >> >> >> -- >> Caution: breathing may be hazardous to your health. >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > Regards, > Sebastian J. > > PS. Please try to bottom-post rather than top-post. Here''s a link I > can advise reading for a clarification on why bottom posting is > essential: http://www.caliburn.nl/topposting.html >Thanks for the heads up about bottom-posting. -- Caution: breathing may be hazardous to your health. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Saturday 07 of August 2010 00:24:08 Leonidas Spyropoulos wrote:> On Fri, Aug 6, 2010 at 7:32 PM, Sebastian ''gonX'' Jensen > > <gonx@overclocked.net> wrote: > > On 6 August 2010 20:23, Leonidas Spyropoulos <artafinde@gmail.com> wrote: > >> Do I have to change the partition ID flag of each partition? > >> Currently is set to fd (Linux Raid autodetect) for used from mdadm > >> mkfs.btrfs supports that or needs to be 83 (Linux) ? > > > > FD is for mdraid integrated into the Linux kernel. I have mine at 83. > > It won''t hurt to have them at FD, but the kernel will spend extra time > > as it probes the devices on boot, causing a slight slowdown. > > Ok done them id 83 and used 3 devices eventually > Using raid0 for data and metadata > # mkfs.btrfs -m raid0 -d raid0 /dev/sdc1 /dev/sdd2 /dev/sde2 > > 2 SATA and 1 ATA drive > I thought that ATA will bottleneck the other 2 drives but seems like I gain > something from it. > Using iozone for benchmark: > # iozone -s 8g -r 1024 -i 0 -i 1 > with 2 SATA devices and then 3 devices (SATA + ATA): > KB reclen write rewrite read reread > 8388608 1024 134869 139607 229146 228800 > 8388608 1024 135151 139050 233461 235929 > > The above is with -o compress option enabled and my cpu topped up on > 100% cpu (both cores) while test and copy huge data. > Is it possible I am bottlenecked by my cpu speed? > AMD Opteron 165 @ 2700 MhzConsidering you have 100% CPU usage during the test, it would seem so.> > >> On Thu, Aug 5, 2010 at 3:40 PM, Hubert Kario <hka@qbs.com.pl> wrote: > >>> On Thursday 05 August 2010 16:15:22 Leonidas Spyropoulos wrote: > >>>> Hi all, > >>>> > >>>> I want to make a btrfs raid0 on 2 partitions of my pc. > >>>> Until now I am using the mdadm tools to make a software raid of the 2 > >>>> partitions /dev/sde2, /dev/sdd2 > >>>> and then mkfs.etx4 the newly created /dev/md0 device. > >>>> From performance point of view is it better to keep the configuration > >>>> of mdadm and just format the /dev/md0 device as btrfs OR > >>>> delete the raid device and format the 2 partitions /dev/sde2 /dev/sdd2 > >>>> as a btrfs with 2 devices? > >>>> mkfs.btrfs /dev/sde2 /dev/sdd2 > >>> > >>> Btrfs already supports metadata mirroring when the data is striped. > >>> What this means, is while the performance should be more-or-less > >>> identical to MD RAID0 (if it isn''t it''s a bug), your data is a bit > >>> more secure as the metadata describing it resides on both drives. > >>> Later on it will be possible to selct which directories/files should > >>> have what level of redundancy. This will allow to have ~/work RAID1-ed > >>> and ~/videos RAID0-ed while keeping both directories on the same > >>> partition and filesystem. > >>> > >>>> On a sidenote: > >>>> If I decide to go for raid5 which is not supported currently from mkfs > >>>> I have to use the mdadm tool anyway, right? > >>> > >>> yes, RAID5 code is not in trunk yet. > >>> > >>> -- > >>> Hubert Kario > >>> QBS - Quality Business Software > >>> 02-656 Warszawa, ul. Ksawerów 30/85 > >>> tel. +48 (22) 646-61-51, 646-74-24 > >>> www.qbs.com.pl > >> > >> -- > >> Caution: breathing may be hazardous to your health. > >> -- > >> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" > >> in the body of a message to majordomo@vger.kernel.org > >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > Regards, > > Sebastian J. > > > > PS. Please try to bottom-post rather than top-post. Here''s a link I > > can advise reading for a clarification on why bottom posting is > > essential: http://www.caliburn.nl/topposting.html > > Thanks for the heads up about bottom-posting.-- Hubert Kario QBS - Quality Business Software 02-656 Warszawa, ul. Ksawerów 30/85 tel. +48 (22) 646-61-51, 646-74-24 www.qbs.com.pl -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 7 August 2010 00:24, Leonidas Spyropoulos <artafinde@gmail.com> wrote:> On Fri, Aug 6, 2010 at 7:32 PM, Sebastian ''gonX'' Jensen > <gonx@overclocked.net> wrote: >> On 6 August 2010 20:23, Leonidas Spyropoulos <artafinde@gmail.com> wrote: >>> Do I have to change the partition ID flag of each partition? >>> Currently is set to fd (Linux Raid autodetect) for used from mdadm >>> mkfs.btrfs supports that or needs to be 83 (Linux) ? >> >> FD is for mdraid integrated into the Linux kernel. I have mine at 83. >> It won''t hurt to have them at FD, but the kernel will spend extra time >> as it probes the devices on boot, causing a slight slowdown. > > Ok done them id 83 and used 3 devices eventually > Using raid0 for data and metadata > # mkfs.btrfs -m raid0 -d raid0 /dev/sdc1 /dev/sdd2 /dev/sde2 > > 2 SATA and 1 ATA drive > I thought that ATA will bottleneck the other 2 drives but seems like I gain > something from it. > Using iozone for benchmark: > # iozone -s 8g -r 1024 -i 0 -i 1 > with 2 SATA devices and then 3 devices (SATA + ATA): > KB reclen write rewrite read reread > 8388608 1024 134869 139607 229146 228800 > 8388608 1024 135151 139050 233461 235929 > > The above is with -o compress option enabled and my cpu topped up on > 100% cpu (both cores) while test and copy huge data. > Is it possible I am bottlenecked by my cpu speed? > AMD Opteron 165 @ 2700 Mhz > >>> >>> On Thu, Aug 5, 2010 at 3:40 PM, Hubert Kario <hka@qbs.com.pl> wrote: >>>> On Thursday 05 August 2010 16:15:22 Leonidas Spyropoulos wrote: >>>>> Hi all, >>>>> >>>>> I want to make a btrfs raid0 on 2 partitions of my pc. >>>>> Until now I am using the mdadm tools to make a software raid of the 2 >>>>> partitions /dev/sde2, /dev/sdd2 >>>>> and then mkfs.etx4 the newly created /dev/md0 device. >>>>> From performance point of view is it better to keep the configuration of >>>>> mdadm and just format the /dev/md0 device as btrfs OR >>>>> delete the raid device and format the 2 partitions /dev/sde2 /dev/sdd2 >>>>> as a btrfs with 2 devices? >>>>> mkfs.btrfs /dev/sde2 /dev/sdd2 >>>> >>>> Btrfs already supports metadata mirroring when the data is striped. What this >>>> means, is while the performance should be more-or-less identical to MD RAID0 >>>> (if it isn''t it''s a bug), your data is a bit more secure as the metadata >>>> describing it resides on both drives. Later on it will be possible to selct >>>> which directories/files should have what level of redundancy. This will allow >>>> to have ~/work RAID1-ed and ~/videos RAID0-ed while keeping both directories >>>> on the same partition and filesystem. >>>> >>>>> On a sidenote: >>>>> If I decide to go for raid5 which is not supported currently from mkfs >>>>> I have to use the mdadm tool anyway, right? >>>> >>>> yes, RAID5 code is not in trunk yet. >>>> >>>> -- >>>> Hubert Kario >>>> QBS - Quality Business Software >>>> 02-656 Warszawa, ul. Ksawerów 30/85 >>>> tel. +48 (22) 646-61-51, 646-74-24 >>>> www.qbs.com.pl >>>> >>> >>> >>> >>> -- >>> Caution: breathing may be hazardous to your health. >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >> >> Regards, >> Sebastian J. >> >> PS. Please try to bottom-post rather than top-post. Here''s a link I >> can advise reading for a clarification on why bottom posting is >> essential: http://www.caliburn.nl/topposting.html >> > Thanks for the heads up about bottom-posting. > > > -- > Caution: breathing may be hazardous to your health. >It seems odd that you are reaching 100% CPU usage. Maybe it''s because I am on an Intel processor with the integrated crc32c module, but with metadata and data striping on 2 decent desktop drives (60 MB/s in avg each on large reads), I don''t go much anywhere near 10% CPU usage, and I have compress-force enabled. I''ve never tried a stress test iozone, but if I can still remember it, I will try to run it once I get back from holidays. Sorry that it doesn''t help your problem, but it seems like it''s something else. I''m assuming you''re running the nForce4 chipset. I don''t recall it being there, but is there an AHCI option for S-ATA in the BIOS, rather than legacy or PATA mode, or something in the lines of that? That could in theory reduce CPU usage somewhat, but shouldn''t really affect anything before very high transfer speeds. And yes, you are bottlenecked if you''re running at max CPU usage. I would try disabling the compress mount option if the above does not help. Regards, Sebastian J. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat, Aug 7, 2010 at 1:03 AM, Sebastian ''gonX'' Jensen <gonx@overclocked.net> wrote:> On 7 August 2010 00:24, Leonidas Spyropoulos <artafinde@gmail.com> wrote: >> On Fri, Aug 6, 2010 at 7:32 PM, Sebastian ''gonX'' Jensen >> <gonx@overclocked.net> wrote: >>> On 6 August 2010 20:23, Leonidas Spyropoulos <artafinde@gmail.com> wrote: >>>> Do I have to change the partition ID flag of each partition? >>>> Currently is set to fd (Linux Raid autodetect) for used from mdadm >>>> mkfs.btrfs supports that or needs to be 83 (Linux) ? >>> >>> FD is for mdraid integrated into the Linux kernel. I have mine at 83. >>> It won''t hurt to have them at FD, but the kernel will spend extra time >>> as it probes the devices on boot, causing a slight slowdown. >> >> Ok done them id 83 and used 3 devices eventually >> Using raid0 for data and metadata >> # mkfs.btrfs -m raid0 -d raid0 /dev/sdc1 /dev/sdd2 /dev/sde2 >> >> 2 SATA and 1 ATA drive >> I thought that ATA will bottleneck the other 2 drives but seems like I gain >> something from it. >> Using iozone for benchmark: >> # iozone -s 8g -r 1024 -i 0 -i 1 >> with 2 SATA devices and then 3 devices (SATA + ATA): >> KB reclen write rewrite read reread >> 8388608 1024 134869 139607 229146 228800 >> 8388608 1024 135151 139050 233461 235929 >> >> The above is with -o compress option enabled and my cpu topped up on >> 100% cpu (both cores) while test and copy huge data. >> Is it possible I am bottlenecked by my cpu speed? >> AMD Opteron 165 @ 2700 Mhz >> >>>> >>>> On Thu, Aug 5, 2010 at 3:40 PM, Hubert Kario <hka@qbs.com.pl> wrote: >>>>> On Thursday 05 August 2010 16:15:22 Leonidas Spyropoulos wrote: >>>>>> Hi all, >>>>>> >>>>>> I want to make a btrfs raid0 on 2 partitions of my pc. >>>>>> Until now I am using the mdadm tools to make a software raid of the 2 >>>>>> partitions /dev/sde2, /dev/sdd2 >>>>>> and then mkfs.etx4 the newly created /dev/md0 device. >>>>>> From performance point of view is it better to keep the configuration of >>>>>> mdadm and just format the /dev/md0 device as btrfs OR >>>>>> delete the raid device and format the 2 partitions /dev/sde2 /dev/sdd2 >>>>>> as a btrfs with 2 devices? >>>>>> mkfs.btrfs /dev/sde2 /dev/sdd2 >>>>> >>>>> Btrfs already supports metadata mirroring when the data is striped. What this >>>>> means, is while the performance should be more-or-less identical to MD RAID0 >>>>> (if it isn''t it''s a bug), your data is a bit more secure as the metadata >>>>> describing it resides on both drives. Later on it will be possible to selct >>>>> which directories/files should have what level of redundancy. This will allow >>>>> to have ~/work RAID1-ed and ~/videos RAID0-ed while keeping both directories >>>>> on the same partition and filesystem. >>>>> >>>>>> On a sidenote: >>>>>> If I decide to go for raid5 which is not supported currently from mkfs >>>>>> I have to use the mdadm tool anyway, right? >>>>> >>>>> yes, RAID5 code is not in trunk yet. >>>>> >>>>> -- >>>>> Hubert Kario >>>>> QBS - Quality Business Software >>>>> 02-656 Warszawa, ul. Ksawerów 30/85 >>>>> tel. +48 (22) 646-61-51, 646-74-24 >>>>> www.qbs.com.pl >>>>> >>>> >>>> >>>> >>>> -- >>>> Caution: breathing may be hazardous to your health. >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>>> >>> >>> Regards, >>> Sebastian J. >>> >>> PS. Please try to bottom-post rather than top-post. Here''s a link I >>> can advise reading for a clarification on why bottom posting is >>> essential: http://www.caliburn.nl/topposting.html >>> >> Thanks for the heads up about bottom-posting. >> >> >> -- >> Caution: breathing may be hazardous to your health. >> > > It seems odd that you are reaching 100% CPU usage. Maybe it''s because > I am on an Intel processor with the integrated crc32c module, but with > metadata and data striping on 2 decent desktop drives (60 MB/s in avg > each on large reads), I don''t go much anywhere near 10% CPU usage, and > I have compress-force enabled. I''ve never tried a stress test iozone, > but if I can still remember it, I will try to run it once I get back > from holidays. Sorry that it doesn''t help your problem, but it seems > like it''s something else.I really doubt my old Opteron has SSE 4.2 and as mentioned from other users it makes a huge difference.> > I''m assuming you''re running the nForce4 chipset. I don''t recall it > being there, but is there an AHCI option for S-ATA in the BIOS, rather > than legacy or PATA mode, or something in the lines of that? That > could in theory reduce CPU usage somewhat, but shouldn''t really affect > anything before very high transfer speeds. >Yes it''s an nForce4 chipset (DFI Expert) And if I recall it''s SATA+PATA mode enabled on mine now. I can''t be sure since I am working on it from ssh.> And yes, you are bottlenecked if you''re running at max CPU usage. I > would try disabling the compress mount option if the above does not > help.After disabling the compress and done the test again it affected the write speed and my CPU wasn''t topped up all the time something like 80-90% results with iozone KB reclen write rewrite read reread 8388608 1024 147736 147062 135427 134744 thanks for that> > Regards, > Sebastian J. >The next step is remove the ATA drive and test again with and without compress mount. -- Caution: breathing may be hazardous to your health. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat, Aug 7, 2010 at 12:16 PM, Leonidas Spyropoulos <artafinde@gmail.com> wrote:> On Sat, Aug 7, 2010 at 1:03 AM, Sebastian ''gonX'' Jensen > <gonx@overclocked.net> wrote: >> On 7 August 2010 00:24, Leonidas Spyropoulos <artafinde@gmail.com> wrote: >>> On Fri, Aug 6, 2010 at 7:32 PM, Sebastian ''gonX'' Jensen >>> <gonx@overclocked.net> wrote: >>>> On 6 August 2010 20:23, Leonidas Spyropoulos <artafinde@gmail.com> wrote: >>>>> Do I have to change the partition ID flag of each partition? >>>>> Currently is set to fd (Linux Raid autodetect) for used from mdadm >>>>> mkfs.btrfs supports that or needs to be 83 (Linux) ? >>>> >>>> FD is for mdraid integrated into the Linux kernel. I have mine at 83. >>>> It won''t hurt to have them at FD, but the kernel will spend extra time >>>> as it probes the devices on boot, causing a slight slowdown. >>> >>> Ok done them id 83 and used 3 devices eventually >>> Using raid0 for data and metadata >>> # mkfs.btrfs -m raid0 -d raid0 /dev/sdc1 /dev/sdd2 /dev/sde2 >>> >>> 2 SATA and 1 ATA drive >>> I thought that ATA will bottleneck the other 2 drives but seems like I gain >>> something from it. >>> Using iozone for benchmark: >>> # iozone -s 8g -r 1024 -i 0 -i 1 >>> with 2 SATA devices and then 3 devices (SATA + ATA): >>> KB reclen write rewrite read reread >>> 8388608 1024 134869 139607 229146 228800 >>> 8388608 1024 135151 139050 233461 235929 >>> >>> The above is with -o compress option enabled and my cpu topped up on >>> 100% cpu (both cores) while test and copy huge data. >>> Is it possible I am bottlenecked by my cpu speed? >>> AMD Opteron 165 @ 2700 Mhz >>> >>>>> >>>>> On Thu, Aug 5, 2010 at 3:40 PM, Hubert Kario <hka@qbs.com.pl> wrote: >>>>>> On Thursday 05 August 2010 16:15:22 Leonidas Spyropoulos wrote: >>>>>>> Hi all, >>>>>>> >>>>>>> I want to make a btrfs raid0 on 2 partitions of my pc. >>>>>>> Until now I am using the mdadm tools to make a software raid of the 2 >>>>>>> partitions /dev/sde2, /dev/sdd2 >>>>>>> and then mkfs.etx4 the newly created /dev/md0 device. >>>>>>> From performance point of view is it better to keep the configuration of >>>>>>> mdadm and just format the /dev/md0 device as btrfs OR >>>>>>> delete the raid device and format the 2 partitions /dev/sde2 /dev/sdd2 >>>>>>> as a btrfs with 2 devices? >>>>>>> mkfs.btrfs /dev/sde2 /dev/sdd2 >>>>>> >>>>>> Btrfs already supports metadata mirroring when the data is striped. What this >>>>>> means, is while the performance should be more-or-less identical to MD RAID0 >>>>>> (if it isn''t it''s a bug), your data is a bit more secure as the metadata >>>>>> describing it resides on both drives. Later on it will be possible to selct >>>>>> which directories/files should have what level of redundancy. This will allow >>>>>> to have ~/work RAID1-ed and ~/videos RAID0-ed while keeping both directories >>>>>> on the same partition and filesystem. >>>>>> >>>>>>> On a sidenote: >>>>>>> If I decide to go for raid5 which is not supported currently from mkfs >>>>>>> I have to use the mdadm tool anyway, right? >>>>>> >>>>>> yes, RAID5 code is not in trunk yet. >>>>>> >>>>>> -- >>>>>> Hubert Kario >>>>>> QBS - Quality Business Software >>>>>> 02-656 Warszawa, ul. Ksawerów 30/85 >>>>>> tel. +48 (22) 646-61-51, 646-74-24 >>>>>> www.qbs.com.pl >>>>>> >>>>> >>>>> >>>>> >>>>> -- >>>>> Caution: breathing may be hazardous to your health. >>>>> -- >>>>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >>>>> the body of a message to majordomo@vger.kernel.org >>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>>>> >>>> >>>> Regards, >>>> Sebastian J. >>>> >>>> PS. Please try to bottom-post rather than top-post. Here''s a link I >>>> can advise reading for a clarification on why bottom posting is >>>> essential: http://www.caliburn.nl/topposting.html >>>> >>> Thanks for the heads up about bottom-posting. >>> >>> >>> -- >>> Caution: breathing may be hazardous to your health. >>> >> >> It seems odd that you are reaching 100% CPU usage. Maybe it''s because >> I am on an Intel processor with the integrated crc32c module, but with >> metadata and data striping on 2 decent desktop drives (60 MB/s in avg >> each on large reads), I don''t go much anywhere near 10% CPU usage, and >> I have compress-force enabled. I''ve never tried a stress test iozone, >> but if I can still remember it, I will try to run it once I get back >> from holidays. Sorry that it doesn''t help your problem, but it seems >> like it''s something else. > > I really doubt my old Opteron has SSE 4.2 and as mentioned from other > users it makes a huge difference. >> >> I''m assuming you''re running the nForce4 chipset. I don''t recall it >> being there, but is there an AHCI option for S-ATA in the BIOS, rather >> than legacy or PATA mode, or something in the lines of that? That >> could in theory reduce CPU usage somewhat, but shouldn''t really affect >> anything before very high transfer speeds. >> > Yes it''s an nForce4 chipset (DFI Expert) > And if I recall it''s SATA+PATA mode enabled on mine now. > I can''t be sure since I am working on it from ssh. > >> And yes, you are bottlenecked if you''re running at max CPU usage. I >> would try disabling the compress mount option if the above does not >> help. > After disabling the compress and done the test again it affected the write speed > and my CPU wasn''t topped up all the time something like 80-90% > results with iozone > KB reclen write rewrite read reread > 8388608 1024 147736 147062 135427 134744 > > thanks for thatI am trying to get the best ration from CPU usage and performance I found out that 2 SATA devices or 2 SATA and 1 ATA devices does not make a lot of difference in performance point of view but some in CPU usage The iozone results for 2 sata devices with compress are KB reclen write rewrite read reread 8388608 1024 138133 135645 166751 164077 and the cpu average topped up at ~100% Avg: 0.2% sy: 76.9% ni: 0.0% hi: 0.0% sy: 1.4% wa: 18.6% On a side note what are the differences of sy: and wa: cpu on cpu usage? Because on 2 sata + 1 ata the sy value was almost all time under 20% and wa value was topped till ~85% What is better? from cpu usage point of view? From performance point of view I would probably keep something that gives me around ~130mb/sec write and ~140mb/sec>> >> Regards, >> Sebastian J. >> > > The next step is remove the ATA drive and test again with and without > compress mount. > > > -- > Caution: breathing may be hazardous to your health. >-- Caution: breathing may be hazardous to your health. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html