Re: [linux-lvm] Is TRIM and DISCARD needed for normal HDD ?
Title: Re: [linux-lvm] Is TRIM and DISCARD needed for normal HDD ? Hi, TRIM is also used on some SMR HDDs. https://superuser.com/questions/1407990/what-does-trim-on-an-hdd-mean Wednesday, November 25, 2020, 16:37:07, you wrote: Hi, I am using thin LVM pools, but I have a normal hard disk and not a SSD. Is there any reason to enable TRIM and/or DISCARD for my HDD ? I have heard it is only useful for a SSD. Will it offer any advantages in my case ? -- Regards, Sreyan Chakravarty -- bYE, Marki ___ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
Re: [linux-lvm] Is TRIM and DISCARD needed for normal HDD ?
Dne 25. 11. 20 v 16:37 Sreyan Chakravarty napsal(a): Hi, I am using thin LVM pools, but I have a normal hard disk and not a SSD. Is there any reason to enable TRIM and/or DISCARD for my HDD ? I have heard it is only useful for a SSD. Will it offer any advantages in my case ? Hi Thin-pool is created by default with 'passdown' TRIM/discard support. This means - discard to thin LV (i.e. fstrim of ext4 on thinLV) gets propagated to thin-pool, where it may deallocate full chunk when possible (i.e. if you use 256K chunk, WHOLE chunk must be free to have an effective discard). With "passdown" mode - such released chunks are also then passed through to origin _tdata device - where again some 'alignment rules' of discardable regions applie (i.e. lot of SSD need 512KiB blocks). If you have HDD - then clearly such discard stops at thin-pool level (automatically) and just releases chunks in thin-pool for future reuse. "ignore" discard mode is usefull in the case you want to keep already 'allocated' chunks for thin LV always there - and also in some case it may make timing more predictible - as discard requires processing - so it ma slowdown few things - but at the expense of more filled thin-pool Hopefully this makes it clear. Regards Zdenek ___ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
[linux-lvm] Is TRIM and DISCARD needed for normal HDD ?
Hi, I am using thin LVM pools, but I have a normal hard disk and not a SSD. Is there any reason to enable TRIM and/or DISCARD for my HDD ? I have heard it is only useful for a SSD. Will it offer any advantages in my case ? -- Regards, Sreyan Chakravarty ___ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
