Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
Gentoo on SSD - any good?
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Installing Gentoo
View previous topic :: View next topic  
Author Message
YPenguin
Apprentice
Apprentice


Joined: 26 Apr 2014
Posts: 277
Location: Kenzingen, Germany

PostPosted: Fri Mar 27, 2015 10:11 am    Post subject: Gentoo on SSD - any good? Reply with quote

Gentoo produces a lot of write traffic with its frequent updates - so it's probably wearing out a SSD quickly?
Back to top
View user's profile Send private message
lexflex
Guru
Guru


Joined: 05 Mar 2006
Posts: 354
Location: the Netherlands

PostPosted: Fri Mar 27, 2015 10:17 am    Post subject: Reply with quote

Hi,

I think modern ssd's can handle quite some read/writes, and you can use a tempfs for the actual building
( http://wiki.gentoo.org/wiki/Portage_TMPDIR_on_tmpfs )

Alex.
Back to top
View user's profile Send private message
eccerr0r
Watchman
Watchman


Joined: 01 Jul 2004
Posts: 7134
Location: almost Mile High in the USA

PostPosted: Fri Mar 27, 2015 5:26 pm    Post subject: Reply with quote

I use PORTAGE_TMPDIR on tmpfs but still compile on ssd if my tmpfs is not big enough (firefox). So far my writes meter barely budged (on the SSDs that have this). Thus I don't think that Gentoo on SSD is a problem.

Currently have three SSD-only machines:
- one with 8GB RAM, 180GB Intel (Sandforce controller) - has enough ram for everything to fit on tmpfs.
- one with 4GB RAM, 240GB Intel (Sandforce controller) - I compile Firefox on the SSD. I formerly had a 128GB Crucial M4, and even that it barely budged after many months of usage - this 128GB Crucial probably had the brunt of the installs as I copied this onto the 240GB disk.
- one with 2GB RAM, 32GB Supertalent (JMicron controller) - This one is *really* well-used (due to age and multiple disk overwrites of data) but haven't gotten any errors yet (knock on wood) over several years of use. Due to the amount of space available, I have to use an external HDD for PORTAGE_TMPDIR. Unfortunately this does not seem to have a write meter so I don't know how much endurance is remaining...

As an experiment I also have a 16GB USB flash drive that I have a full Gentoo installed (not liveusb, it actually boots full Gentoo and I can emerge stuff on it). I wonder how long this will last. It's really slow unfortunately. We'll see...
_________________
Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSD
What am I supposed watching?
Back to top
View user's profile Send private message
albright
Advocate
Advocate


Joined: 16 Nov 2003
Posts: 2541
Location: Near Toronto

PostPosted: Fri Mar 27, 2015 6:43 pm    Post subject: Reply with quote

Quote:
I think modern ssd's can handle quite some read/writes


yeah, like 2400 terabytes!

(see http://techreport.com/review/27909/the-ssd-endurance-experiment-theyre-all-dead)

SSDs eat gentoo for breakfast :)
_________________
.... there is nothing - absolutely nothing - half so much worth
doing as simply messing about with Linux ...
(apologies to Kenneth Graeme)
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 43213
Location: 56N 3W

PostPosted: Fri Mar 27, 2015 9:51 pm    Post subject: Reply with quote

YPenguin,

The days of a Gentoo install on a 4G or 8G eeepc killing the SSD before the install was complete are long past.
SSDs have got bigger, have wear levelling, so the wear is spread over a larger area.

My wifes PC is 256G M4 only and it seems to be OK. Its two years old and is updated monthly.
It PC is older but it was diskless before SSDs got a a reasonable price/performance point.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
Barracuz
n00b
n00b


Joined: 17 Mar 2015
Posts: 17
Location: R.I., United States

PostPosted: Wed Apr 01, 2015 1:46 pm    Post subject: Reply with quote

So using an ssd won't be an issue with gentoo correct

Also what would be a good ssd to use? I've seen many ssds online with diffrent specs: diffrent write speeds, internal ram or space for temp writing?

Anything specific to look out for or is it just a matter of getting the biggest ssd you can afford?
EBay currently had a 1tb samsung msata ssd for 350 buckaroos. Almost bought it.

Also sorry if I'm hijacking the thread, this one seems fit for my question.
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 43213
Location: 56N 3W

PostPosted: Wed Apr 01, 2015 5:53 pm    Post subject: Reply with quote

Barracuz,

Big is only good if you will actually use the space.
It will give the wear levelling more room to work but faster drives will be around before you wear it out anyway.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
Ant P.
Watchman
Watchman


Joined: 18 Apr 2009
Posts: 5765

PostPosted: Wed Apr 01, 2015 6:04 pm    Post subject: Reply with quote

Avoid MLC (multi-level cell) drives; they make extreme tradeoffs of durability for capacity, stories of them failing after a month of average OS use (not even Gentoo) aren't unheard of. Single/Two-Level-Cell flash is fine. Always read around for other people's experiences, there have been a few drives released with broken firmware.
Back to top
View user's profile Send private message
eccerr0r
Watchman
Watchman


Joined: 01 Jul 2004
Posts: 7134
Location: almost Mile High in the USA

PostPosted: Wed Apr 01, 2015 10:54 pm    Post subject: Reply with quote

All of my SSDs are MLC (2 bit per cell) and they are fine. The controllers have come a long way since the first revisions and do wear leveling correctly. Finding SLC drives is hard nowadays, at least the expense of them tend to push them out of range. But broken firmware is always something to look out for - however, even this, most recent SSDs have that wrinkle ironed out.

Maybe someone needs to do a

Code:
#!/bin/bash
declare -i count
count=0
while emerge -e @world; do
count=count+1
done
echo we survived $count empty world builds\!


and see how many times it will run before the SSD dies... like what those ssd killers did...

:p
_________________
Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSD
What am I supposed watching?
Back to top
View user's profile Send private message
javeree
Guru
Guru


Joined: 29 Jan 2006
Posts: 349

PostPosted: Thu Apr 02, 2015 12:02 pm    Post subject: Reply with quote

@eccerr0r

I ran a small gentoo System on USB Flash, two years back, running regular updates (every 2-5 days). It died in half a year.
Back to top
View user's profile Send private message
augustin
Guru
Guru


Joined: 23 Feb 2015
Posts: 318

PostPosted: Thu Apr 02, 2015 1:22 pm    Post subject: Reply with quote

In this thread and elsewhere, I see many contradicting reports about the reliability of SSD drives.
Some say that it's no longer an issue in real-life use, but others see their SSD drives die.

I'm confused and don't know whom to believe. I'd like to build an SSD-only system (/, /home /usr /var, /etc /tmp, etc.) with an extra HDD only for large media files (movies, etc.). But I'm worried about reliability (backups notwithstanding).
Back to top
View user's profile Send private message
dab_s_bad
n00b
n00b


Joined: 08 May 2008
Posts: 54
Location: Toledo City, Cebu, Philippines

PostPosted: Thu Apr 02, 2015 1:47 pm    Post subject: Reply with quote

augustin wrote:
In this thread and elsewhere, I see many contradicting reports about the reliability of SSD drives.
Some say that it's no longer an issue in real-life use, but others see their SSD drives die.

I'm confused and don't know whom to believe. I'd like to build an SSD-only system (/, /home /usr /var, /etc /tmp, etc.) with an extra HDD only for large media files (movies, etc.). But I'm worried about reliability (backups notwithstanding).


My Advice..., since you are confused..., just heed all 'pre-cautions' and you'll get all the good sides (mostly ^_^ )
for me, I will take note of the bad things and pray and luck for the device not to get quirky ^_^
Back to top
View user's profile Send private message
eccerr0r
Watchman
Watchman


Joined: 01 Jul 2004
Posts: 7134
Location: almost Mile High in the USA

PostPosted: Thu Apr 02, 2015 2:24 pm    Post subject: Reply with quote

USB flash, especially noname cheap ones, are MUCH less reliable than modern SSDs as they have limited controllers. But regardless I've actually done just that for fun: I've installed Gentoo to a 16GB USB flash (Lexar branded) and to see how long that lasts. Unfortunately that thing is so slow that I can't bear to use that as a main disk since I've been so spoiled by SATA SSD performance, though it is OK in a pinch. But so far it has survived a few emerge --sync and emerge world updates. I'd imagine the number of spare cells on this USB flash drive isn't as large nor the wear levelling as advanced as a SATA SSD so I doubt it will last as long.

I also have a 16GB MicroSD card (incidentally, also made by Lexar) that I've rsynced a Gentoo install onto many times. Though it also has a full Gentoo install on it, I'm not emerging on it because it's way too slow (Class 4). This is even after the fact that I've had many SD cards that croaked after a bit of use.

But I'd have to say that the regular full sized SSDs that I have - they're really good. I was a bit hesitant at first but I bought them anyway and now I really have no fears on modern SATA SSDs. I did get the Intel and Crucial SSDs because they have a 5 or 3 year warranty respectively. However, based by anecdotal evidence, I'd buy Samsung or other brands as well, I think they've matured enough to be trustable. But it doesn't matter what SSD I have, I still backup, whether it's to another SSD or HDD or tape or whatever, SSD does not mean you never have to worry about backups.

But everyone is still allowed to have their own opinions of course. I took the plunge and am happy with the SATA SSDs. The USB and SD media I'm not so much yet, but that's a different media.

Digging up an old poll: https://forums.gentoo.org/viewtopic-t-1008866.html
_________________
Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSD
What am I supposed watching?
Back to top
View user's profile Send private message
augustin
Guru
Guru


Joined: 23 Feb 2015
Posts: 318

PostPosted: Thu Apr 02, 2015 3:06 pm    Post subject: Reply with quote

@dab_s_bad Thanks. I certainly plan to follow your advice.

@eccerr0r Many thanks for your insight. You make an interesting point about the importance of controllers (spare cells, wear-levelling algorithm, etc.).

This begs the question:

With regard to the quality of the controller, what differences would there be between a traditional SATA SSD, and new generation SAS, M.2 or PCIe SSD drives?
Back to top
View user's profile Send private message
Ant P.
Watchman
Watchman


Joined: 18 Apr 2009
Posts: 5765

PostPosted: Thu Apr 02, 2015 3:43 pm    Post subject: Reply with quote

eccerr0r wrote:
All of my SSDs are MLC (2 bit per cell) and they are fine.

That's what I said. Single and two level flash is okay, it's numbers higher than that where things go wrong fast. I have two 2LC drives myself.
Back to top
View user's profile Send private message
augustin
Guru
Guru


Joined: 23 Feb 2015
Posts: 318

PostPosted: Thu Apr 02, 2015 3:57 pm    Post subject: Reply with quote

augustin wrote:

With regard to the quality of the controller, what differences would there be between a traditional SATA SSD, and new generation SAS, M.2 or PCIe SSD drives?


What I mean is that SATA SSD look like what they are: drives! They are a kind of box with connectors, and which contain cells and God knows what else inside (I guess their manufacturers do!).

With the newest stuff (M.2, PCIe, etc.), the SSDrives no longer look like drives but more like RAM sticks. What hardware did they leave out compared to standard SATA drives? Did they leave out controllers, firmware, extra cells...? The performance is impressive, but what about the long term reliability?
Back to top
View user's profile Send private message
eccerr0r
Watchman
Watchman


Joined: 01 Jul 2004
Posts: 7134
Location: almost Mile High in the USA

PostPosted: Thu Apr 02, 2015 5:36 pm    Post subject: Reply with quote

Ant P. wrote:
eccerr0r wrote:
All of my SSDs are MLC (2 bit per cell) and they are fine.

That's what I said. Single and two level flash is okay, it's numbers higher than that where things go wrong fast. I have two 2LC drives myself.

"2" level means single bit for me (high and low levels, binary bit; I'm thinking about the voltages stored within the flash cell versus bits)... hence I was confused at your statement.

The usual terminology for MLC ("multi level cell") flash is actually 4-level or 2-bit per cell. By themselves they're not great, but modern controllers compensate very well. The 8-level/3-bit per cell are scary, and not sure I quite trust it yet, but even these are well compensated by their controllers. It is true that the becoming-more-rare one cell per bit so called "SLC" flash are more reliable - but that's by itself without a controller to back it up. I have some Smartmedia that is SLC rated for 100000 write/erase cycles. However with the lack of a controller limits its usability to 100000 cycles - once the "critical areas" wear out, it's done. But even for the lower 3000 cycle MLCs, the controller will not use the same areas for the "critical" areas over and over again, and thus will last a lot longer. Granted a good control AND single bit per cell flash would be the best of both worlds, and the lifetime may far exceed the useful storage capacity of the drive.

The "newest" stuff still need to deal with the same problems as SATA SSDs flash chips. I do kind of wonder if they really look like RAM to the CPU, they may be like the old venereable "winmodems" where the main CPU manages the wear levelling...
_________________
Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSD
What am I supposed watching?
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 43213
Location: 56N 3W

PostPosted: Fri Apr 03, 2015 3:45 pm    Post subject: Reply with quote

augustin,

augustin wrote:
What I mean is that SATA SSD look like what they are: drives! They are a kind of box with connectors, and which contain cells and God knows what else inside (I guess their manufacturers do!).

With the newest stuff (M.2, PCIe, etc.), the SSDrives no longer look like drives but more like RAM sticks. What hardware did they leave out compared to standard SATA drives? Did they leave out controllers, firmware, extra cells...? The performance is impressive, but what about the long term reliability?


Its just the interface thats different. If you care to design the electronics you can have any interface you want ... floppy drive, SCSI, SATA, PATA, ST-502, USB, Parallel Port, Centronics, serial port, firewire, Raspberry Pi GPIO, SD, micro SD, PCMCIA, PC Card ...
Of course, some of the interfaces in that list are long forgotten, or don't make sense (or both). But the guts of the SSD are unchanged by the interface it presents to the outside world.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
augustin
Guru
Guru


Joined: 23 Feb 2015
Posts: 318

PostPosted: Fri Apr 03, 2015 4:02 pm    Post subject: Reply with quote

Thanks, NeddySeagoon.

So I guess that the firmware and the controllers and whatnots fit on what little hardware remains in the M.2 SSD.
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 43213
Location: 56N 3W

PostPosted: Fri Apr 03, 2015 5:14 pm    Post subject: Reply with quote

augustin,

The firmware could be uploaded by the driver, which would save the cost of the FLASH ROM in which to store it, like so many USB devices.
The controller is probably present in hardware as it needs to be very fast. It could also be uploaded into a FPGA at start up, that would be similar to CPU microcode, which has to operate at the CPU core clock speed and be non volitile.
Its stored in (slow) non volitile memery in the CPU and moved to RAM on the CPU for actul use.
The controller will be there somehow.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
augustin
Guru
Guru


Joined: 23 Feb 2015
Posts: 318

PostPosted: Fri Apr 03, 2015 6:31 pm    Post subject: Reply with quote

Oh, OK.

Thanks a lot.

And thanks for your patience with my newbie questions! ;)
Back to top
View user's profile Send private message
YPenguin
Apprentice
Apprentice


Joined: 26 Apr 2014
Posts: 277
Location: Kenzingen, Germany

PostPosted: Fri Apr 17, 2015 8:59 am    Post subject: Sshd Reply with quote

Has anyone of you a SSHD?
Back to top
View user's profile Send private message
eccerr0r
Watchman
Watchman


Joined: 01 Jul 2004
Posts: 7134
Location: almost Mile High in the USA

PostPosted: Fri Apr 17, 2015 4:34 pm    Post subject: Reply with quote

They should work fine but watch out for the ones that require drivers.
You can get similar effects in software with Linux's caching software but I haven't actually used either of these, I just used pure SSD solutions.
_________________
Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSD
What am I supposed watching?
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Installing Gentoo All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum