[SLUG] dd speed (copying whole disks)
>Dont know anything about *DMA stuff... Try this URL http://www.storagereview.com/guide2000/ref/hdd/if/ide/modesUDMA.html -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] dd speed (copying whole disks)
On Wed Dec 17, 2003 at 13:14:46 +1100, Simon Males wrote: > >PS i just moved here from the digest, could like the list have 'reply to >list' switched on?! > I take this time to introduce members to our wonderful FAQ which is at: http://www.slug.org.au/faq/, and in particular http://www.slug.org.au/faq/mailinglists.html#q9. Cheers, Benno -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
Re: [SLUG] dd speed (copying whole disks)
Im copying 40g drive onto a 120g drive. I am using a CD live type linux distro. Which is SystemRescueCd I have a little theory that running top may freeze the process, because since running top once, the dd or cat process cpu time has not changed. I think my theory pulled through. I ran dd and didnt touch it and the job was done in 45mins. I then ran qtparted (run_qtparted on the CD) to resize it GUI magically. I didnt use cpio because it was NTFS. What took me 4 days initially will take me an hour now. PS i just moved here from the digest, could like the list have 'reply to list' switched on?! -- Simon Males <[EMAIL PROTECTED]> No More AOL CDs Australia - www.anticd.org -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
Re: [SLUG] dd speed (copying whole disks)
On Tue, 2003-12-16 at 22:24, [EMAIL PROTECTED] wrote: > On Tue, 16 Dec 2003 17:12:24 +1100 > Bret Comstock Waldow <[EMAIL PROTECTED]> wrote: > > > My 20G disk copies in 2 hours and 40 minutes. I've experimented with > > Mine took 15 minutes for 6.4Gb. (athlon 1700+, dma4 disks) > > Why do people dd disks anyway. In my case it's my backup method, so duplicates are in fact the idea in the first place. > There's a few pitfalls > such as duplicate serial numbers, duplicate mac addresses. > (yes, sometimes mac addresses are stored in file base configuration) > > tar/dump/cpio are faster and more flexible. dd gets any partition changes I've made. I'm using PartitionMagic, and slowly shrinking my Window$ partition, and occassionally making other changes. > > Matt > ps. i had a specific data recovery purpose in my exercise Me too. Cheers, Bret -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
Re: [SLUG] dd speed (copying whole disks)
On Tue, 16 Dec 2003 17:12:24 +1100 Bret Comstock Waldow <[EMAIL PROTECTED]> wrote: > My 20G disk copies in 2 hours and 40 minutes. I've experimented with Mine took 15 minutes for 6.4Gb. (athlon 1700+, dma4 disks) Why do people dd disks anyway. There's a few pitfalls such as duplicate serial numbers, duplicate mac addresses. (yes, sometimes mac addresses are stored in file base configuration) tar/dump/cpio are faster and more flexible. Matt ps. i had a specific data recovery purpose in my exercise -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
Re: [SLUG] dd speed (copying whole disks)
My situation is a bit different - I'm copying between identical drives. I wonder if geometry translation might be a factor? Also, are both drives IDE and on the same channel (both Primary or both Secondary)? Given you're reporting hda and hdc I suspect no. The other device on the channel (like a slow CD) will limit the disk to it's limit, so maybe that's slowing down hdc in your case. I copy hda to hdc, but I have no hdb or hdd at the same time, so both channels run at the disk's full speed(s). My 20G disk copies in 2 hours and 40 minutes. I've experimented with different bs= settings, and haven't noted much variance between them. I run "date; dd if=/dev/hda of=/dev/hdc bs=16384k; date". Someone suggested I use "time" but my Tom's RootBoot diskette doesn't include "time". Cheers, Bret On Mon, 2003-12-15 at 10:58, Simon Males wrote: > Im copying 40g drive onto a 120g drive. I am using a CD live type linux > distro. > > using the command > > # dd if=/dev/hda of=/dev/hdc bs=2048k > > The thing is I dont know if its working, dd gives no active feedback. I > dont think i could even ^C it. I left it running for some >12hrs, hard > reboot, jumped back to fdisk and a partition table was written of some > sort (well there was a hdc1 now, just like how there was only hda1). It > was fresh from the shop, so the disk was completely blank. > > First time i tried, while dd was running I did a `fdisk -l /dev/hdc` and > I was given constant hdc errors. So basically can I query the > destination the disk and see...something?! > > Further, is > > # cat /dev/hda > /dev/hdc > > slower than doing the above dd command? I've had cat running for around > 22hrs now. > > I have a little theory that running top may freeze the process, because > since running top once, the dd or cat process cpu time has not changed. > > -- > Simon Males <[EMAIL PROTECTED]> > No More AOL CDs Australia - www.anticd.org -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
Re: [SLUG] dd speed (copying whole disks)
Simon Males wrote: Im copying 40g drive onto a 120g drive. I am using a CD live type linux distro. you could use partimage and ext2resize. www.partimage.org dave -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
Re: [SLUG] dd speed (copying whole disks)
We should point out that this method is only close to efficient when the source disk is nearly full of data. This is because you're copying the blank space too. Still, if you're happy to leave it running over a weekend it's the easiest way to get the lot. The other way if you're savvy and in a hurry is to manually use fdisk to create the partitions, then mke2fs (or whatever fs you're using) the partitions then mount & copy the files using cpio or something. On Mon, 15 Dec 2003, Dave Airlie wrote: > > should be good enough at udma2/5, 5 relies on the 80-pin cable and I'd say > the secondary i/f isn't udma5 capable.. > > so it shouldn't take a major amount of time to copy a drive with those > setings... (not sure exactly how long ...) > > Dave. > > On Mon, 15 Dec 2003, Simon Males wrote: > > > > > Dont know anything about *DMA stuff... > > > > /dev/hda > > DMA modes: mdma0 mdma1 mdma2 > > UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5 > > > > /dev/hdc > > DMA modes: mdma0 mdma1 mdma2 > > UDMA modes: udma0 udma1 *udma2 udma3 udma4 udma5 > > > > I guess "udma2" is bad?! > > > > -- > > Simon Males <[EMAIL PROTECTED]> > > No More AOL CDs Australia - www.anticd.org > > > > Dave Airlie wrote: > > > Check that you have DMA switched on both drivers with hdparm .. > > > > > > otherwise this could take a long time :-) > > > > > > Dave. > > > > > > > -- -- Electronic Hobbyist, Former Arcadia BBS nut, Occasional nudist, Linux Guru, SLUG/AUUG/Linux Australia member, Sydney Flashmobber, BMX rider, Walker, Raver & rave music lover, Big kid that refuses to grow up. I'd make a good family pet, take me home today! Do people actually read these things? -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
Re: [SLUG] dd speed (copying whole disks)
should be good enough at udma2/5, 5 relies on the 80-pin cable and I'd say the secondary i/f isn't udma5 capable.. so it shouldn't take a major amount of time to copy a drive with those setings... (not sure exactly how long ...) Dave. On Mon, 15 Dec 2003, Simon Males wrote: > > Dont know anything about *DMA stuff... > > /dev/hda > DMA modes: mdma0 mdma1 mdma2 > UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5 > > /dev/hdc > DMA modes: mdma0 mdma1 mdma2 > UDMA modes: udma0 udma1 *udma2 udma3 udma4 udma5 > > I guess "udma2" is bad?! > > -- > Simon Males <[EMAIL PROTECTED]> > No More AOL CDs Australia - www.anticd.org > > Dave Airlie wrote: > > Check that you have DMA switched on both drivers with hdparm .. > > > > otherwise this could take a long time :-) > > > > Dave. > > > -- David Airlie, Software Engineer http://www.skynet.ie/~airlied / airlied at skynet.ie pam_smb / Linux DECstation / Linux VAX / ILUG person -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
Re: [SLUG] dd speed (copying whole disks)
Dont know anything about *DMA stuff... /dev/hda DMA modes: mdma0 mdma1 mdma2 UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5 /dev/hdc DMA modes: mdma0 mdma1 mdma2 UDMA modes: udma0 udma1 *udma2 udma3 udma4 udma5 I guess "udma2" is bad?! -- Simon Males <[EMAIL PROTECTED]> No More AOL CDs Australia - www.anticd.org Dave Airlie wrote: Check that you have DMA switched on both drivers with hdparm .. otherwise this could take a long time :-) Dave. -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
Re: [SLUG] dd speed (copying whole disks)
Check that you have DMA switched on both drivers with hdparm .. otherwise this could take a long time :-) Dave. On Mon, 15 Dec 2003, Simon Males wrote: > Im copying 40g drive onto a 120g drive. I am using a CD live type linux > distro. > > using the command > > # dd if=/dev/hda of=/dev/hdc bs=2048k > > The thing is I dont know if its working, dd gives no active feedback. I > dont think i could even ^C it. I left it running for some >12hrs, hard > reboot, jumped back to fdisk and a partition table was written of some > sort (well there was a hdc1 now, just like how there was only hda1). It > was fresh from the shop, so the disk was completely blank. > > First time i tried, while dd was running I did a `fdisk -l /dev/hdc` and > I was given constant hdc errors. So basically can I query the > destination the disk and see...something?! > > Further, is > > # cat /dev/hda > /dev/hdc > > slower than doing the above dd command? I've had cat running for around > 22hrs now. > > I have a little theory that running top may freeze the process, because > since running top once, the dd or cat process cpu time has not changed. > > -- David Airlie, Software Engineer http://www.skynet.ie/~airlied / airlied at skynet.ie pam_smb / Linux DECstation / Linux VAX / ILUG person -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
[SLUG] dd speed (copying whole disks)
Im copying 40g drive onto a 120g drive. I am using a CD live type linux distro. using the command # dd if=/dev/hda of=/dev/hdc bs=2048k The thing is I dont know if its working, dd gives no active feedback. I dont think i could even ^C it. I left it running for some >12hrs, hard reboot, jumped back to fdisk and a partition table was written of some sort (well there was a hdc1 now, just like how there was only hda1). It was fresh from the shop, so the disk was completely blank. First time i tried, while dd was running I did a `fdisk -l /dev/hdc` and I was given constant hdc errors. So basically can I query the destination the disk and see...something?! Further, is # cat /dev/hda > /dev/hdc slower than doing the above dd command? I've had cat running for around 22hrs now. I have a little theory that running top may freeze the process, because since running top once, the dd or cat process cpu time has not changed. -- Simon Males <[EMAIL PROTECTED]> No More AOL CDs Australia - www.anticd.org -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
