RE: [gentoo-user] planning a new machine : comments welcome

[Laurence Perkins]

>
>
> -----Original Message-----
> From: Dale <rdalek1967@×××××.com>
> Sent: Wednesday, March 2, 2022 5:08 PM
> To: gentoo-user@l.g.o
> Subject: Re: [gentoo-user] planning a new machine : comments welcome
>
> Laurence Perkins wrote:
> > With regard to SMR drives, note that there are three basic types:
> >
> > Some completely hide the fact that they are SMR.  These suck, hands down.  Performance is unpredictable and random.
> > Some at least advertise that they're SMR, and expose basic counters about where they are in their maintenance cycles.  These still suck, but at least you can kind of predict when they're about to get really slow.
> >
> > The best ones actually advertise what the shingled ranges are, at which point a new enough kernel and filesystem can keep the writes to those ranges as sequential as possible, and you can use the big, cheap drives with very little performance loss.
> >
> > There are a couple articles explaining how to determine what you've got and optimize it.  I don't have my bookmarks to hand, but it was in a discussion on this list a few months ago.
> >
> > LMP
> >
>
> That's some new info.  I tend to follow threads, even started one ages ago about my hard drive doing a bumpy thing for a long time after I updated my backups.  Rich plus others informed me I unknowingly bought a SMR drive.  I think mine has about a 15 or 20GB CMR section.  I've noticed if my updates go to about that much or more, it gets slow. Either way, it does the bumpy thing for a good while after my backups are done and I've unmounted the drive.  I just let it sit there until it gets done.  If I don't, it just slows down faster the next time because it starts out behind on moving the files from CMR to SMR and doing its rewrite thing.
>
> My biggest point for the OP, look at its use and pick what works as expected.  I've read, and Wol seems to confirm this, that RAID and SMR do not go together well.  I've read some have hosed RAID thingys when they put in a SMR drive and didn't know it.
>
> The biggest problem I have is when they don't let us know when a drive is SMR.  I don't like a company that sells me something that isn't as good without telling me.  It sort of rubs me the wrong way.
>
> To the OP tho, research first, then buy.  Know what you getting and that it will work for your needs.  As I said, for the most part, my backup drive being SMR is mostly a little annoying.  It does work.  I just won't do it again tho.
>
> Dale
>
> :-)  :-)
>
>


Yeah, A lot of RAID controllers will see the bumpy performance and error out.  Some vendors are starting to update their firmware though.

You're not alone in being upset about manufacturers trying to sneak SMR in without telling anyone.  The CCTV industry kind of took them to the woodshed over it.

BTRFS got patches for detecting and optimizing zoned drives in 2020.  

EXT4 has a format-time option for it at this point.  

F2FS and NILFS2 are both designed to write a disk end-to-end sequentially for wear-levelling purpose and while they're not the fastest, they also don't see significant performance degradation from SMR except during schedulable maintenance operations.

https://zonedstorage.io/ has a good list of reference material for figuring out what you've got and getting it configured in the best way.



LMP