SSD performance problems -- config problem or old drive?

[oshunluvr]

Looks like both Reaper and Davinci have Linux versions...jus' sayin'

[chconnor]

Looks like both Reaper and Davinci have Linux versions...jus' sayin'

Totally, and I'm thrilled that they do... unfortunately I use a bunch of VST plugins in Reaper that are windows only... you can run a few of them via wine bridges in linux, but they are way too slow... and the ones that don't run at all are crucial to my work. I use Reaper in linux for tracking, but when it comes time to mix, it's back to dumb ol' windows. Resolve in linux can't export to h.264, can't import h.264 (in the free version), has no aac support, no mp3 support (I think? at least in the free version? been a while since I went through all that) which all make it impractical to use, quite unfortunately. If I used it more I might ante up the cash for the paid version.

Believe me I'll get rid of that windows partition the minute I can! :-)

[oshunluvr]

Yes...

I will say the audio here is rather crappy, so may not be an option for you.

[chconnor]

That's cool, I'm mostly interested to use the VM idea for some development I may be doing that will require a Win install. My window partition is low on space, visual studio takes enormous amounts of space, and moving windows installations from partition to partition is so confusing and fraught and hard to research that i'd rather just get a new Win 10 going in a VM with one of those sketchy cheap licenses... I'm glad you brought it up because i was contemplating buying a new drive for this purpose, but a VM sounds nicer.

[GreyGeek]

Are your disks getting full? I.e., over 90%?

[chconnor]

Yes -- / is 94%, /home is 85%, the "other partition" mentioned above is 8% (all on the same physical drive). I suffer from chronic "partitions too small" syndrome. The next computer I make will have 10x too-large partitions.

The drive is under-partitioned though, for whatever it's worth: 128GB drive, with ~23 GB unallocated.

[chconnor]

$ findmnt /dev/sda2
TARGET SOURCE FSTYPE OPTIONS
/ /dev/sda2 ext4 rw,noatime,nobarrier,errors=remount-ro,commit=60

...I expected "data=writeback" in there... /etc/fstab is:

UUID=1234 / ext4 noatime,data=writeback,barrier=0,nobh,commit=60,er rors=remount-ro 0 1

...any ideas? I notice that "nobh" also seems to be disappearing. Should I just ignore these issues and trust that data=writeback and nobh are in effect?

"journalctl -xb" seems to have answered these questions:

EXT4-fs (sda2): Ignoring removed nobh option
EXT4-fs (sda2): re-mounted. Opts: data=writeback,barrier=0,nobh,commit=60,errors=remount-ro

Seems odd that data=writeback doesn't show up in findmnt, but i dunno...

[oshunluvr]

Maybe it's just me, but unless your / partition is gigantic, 94% is danger close to a broken install IMO. It's a small matter to have a data partition fill up but a 100% / or even /home can wreak havoc. This might account for a bit of the slowness too.

There's no reason I know of to not allocate all the space on the drive to partitions. This is a years old held-over concept that no longer applies (and maybe never did). Unallocated space is not used by the system or drive and has no purpose. This is not the same as a drive with built-in over-provisioning in which the drive controller manages some extra sectors, but I don't think they even do that anymore. The drive controller will take care of bad sectors by marking them as unusable.

Unfortunately, as long as you continue to use EXT4 you will have to guess at your partition sizes. It's been years since I had to do that, but you could create an additional partition in that free space and move some folder onto it without having to re-partition the entire drive. /var and /opt were commonly on separate partitions in the "olden days" of Linux - from which I come, lol. My /var is about 8G right now. /opt can get large is you have lots of non-ubuntu based programs installed, but mines only about 2G

Another thing you can do is move /tmp to RAM. You don't mention a swap partition so if you're using a swap file, you can easily move that by deleting and re-creating it elsewhere.

[chconnor]

Yeah I keep a pretty tight control on the / size so I don't run out of space. But I didn't realize it could have a negative impact on speed, so I'll try to claw back some more free space and see if that helps.

Re: reserving space -- I was led to believe that it was still useful for the 840 Pro, at least of the era? E.g. this article (2012, which is roughly when I got the drive) seems to conclude that there are pretty clear benefits to it: "Vector and Samsung's SSD 840 Pro both deliver much better IO consistency if you simply set aside 25% of the total NAND capacity as spare area."

swap is encrypted, but on a slower HDD (I have 16GB RAM, so hopefully it's not used much?)

/tmp is already a ram disk, but thanks for that tip.

[oshunluvr]

Overprovisioning will supposedly help performance, but a nearly full file system will definitely slow it. There USED TO BE a Samsung utility to allow the user to adjust the amount of provisioned space. Samsung has removed the over-provisioning tool from their software: https://community.spiceworks.com/top...d-space-on-ssd.

It's a dilemma for sure. Just my opinion here, but it you have been working to keep your root fs from filling up and are likely experiencing speed reductions due to it being over 90% capacity, https://www.howtogeek.com/165542/why...-fill-them-up/

Seems to me you've possibly overlooked your own actual experience in favor of advise from 2012 that probably doesn't even apply anymore, if it ever did. They knew very little about the actual use-cases for SSDs as they were still pretty new to the consumer market. About half the stuff I've read really applies to the enterprise environment. They used to (and some still do) advise against keeping swap on an SSD. Totally counter to logic IMO. Why spend the money to increase performance then purposely slow down the performance by not using the fastest device for the slowest operation? Makes no sense at all. They talk about wearing it out but I'm still using the first SSD I bought more than a decade ago as my server OS drive. It's way past it's usability date yet keeps on going. Why have something then not use it? /rant The highest wear factor is running trim to often.

For what it's worth, I have been using SSDs since 2010 or so and currently have more than 10 of them in various types, uses. and computers and have never left space any on them unformatted. My two 840 Pros are 100% partitioned and about 75% full and both outperform yours - not by much, but more than zero. I'm just saying in my experience a file system with free space is a larger benefit than unused space doing apparently nothing.

BTW, you seem like a sharp user but in case you weren't aware; the EXT file system by default keeps a 5% reserved amount of space for "system use" that really only apply to a file system that's has the OS on it. When I use EXT for data partitions like /home I reduce the reserved amount to zero and if you have an OS on it and it's a large partition, I shrink the reserved to 1-2%

To see what you've reserved:

sudo tune2fs -l /dev/<partition> | grep 'Reserved'

and to adjust it:

sudo tune2fs -m2 /dev/<partition>

The "-m2" meaning "set reserved at 2%"

[oshunluvr]

Pulled this from somewhere:

All SSD have overprovsioning. Samsung 840 Pro is sold with 256,000,000,000 Bytes space, but there are 256 GiBi build in which are 274,877,906,944 Bytes. There are 7% internal overprovisioning and there is no need to do overprovisioning. The Samsung tool only creates a partition which is smaller then the total size.
I would just use the SSD as a hard drive and try to keep at least 10% free or more.

[chconnor]

Thanks for the perspectives. I did read up on that "reserved block" issue as well, thanks.

[oshunluvr]

Yeah, good conversation. Let us know if you get the slowness issue resolved.

[GreyGeek]

What Oshunluver said, AND ... EXT4 is getting long in the tooth. Isn't it about time to move to a modern, advanced FS where you don't have to worry about partition sizes, and backups are almost instantaneous?

[chconnor]

Last I heard on btrfs (which was some years ago now) things were still a little sketchy... (I got all excited from Jim Salter's articles on arstechnica, but then he later advised against using it for important stuff until issues got worked out...) Is it all-clear now?