a solid-state disk (SSD)

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48
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3answers
4k views

What NOT to put on an SSD?

I bought an SSD and I am going to set up my desktop system with a completely fresh Linux installation. SSDs are known to be fast, but they have a disadvantage: The number of writes (per block?) is ...
36
votes
3answers
23k views

How to know if a disk is an SSD or an HDD

I want to know whether a disk is a solid-state drive or hard disk. lshw is not installed. I do yum install lshw and it says there is no package named lshw. I do not know which version of ...
23
votes
3answers
23k views

How can I safely remove a SATA disk from a running system?

I sometimes need to plug a disk into a disk bay. At other times, I have the very weird setup of connecting a SSD using a SATA-eSATA cable on my laptop while pulling power from a desktop. How can I ...
18
votes
7answers
6k views

Linux equivalent to ReadyBoost?

Is there a kernel module or some other patch or something similar to Windows' ReadyBoost? Basically I'm looking for something that allows disk reads to be cached on a Flash drive.
17
votes
4answers
2k views

File system for an SSD drive

I always thought that traditional file systems, are geared and optimized for non-ssd drive, where, for instance, data locality is important, and fragmentation is problematic. Is there a file system ...
11
votes
2answers
1k views

Heavy write activity on SSD nukes system performance

I've noticed that when I do heavy write applications, the whole system slows down. To test this further I ran this to do a (relatively) low-CPU, high disk activity: john -incremental > file_on_SSD ...
10
votes
3answers
3k views

Trim with LVM and dm-crypt

I tried to setup TRIM with LVM and dm-crypt on ubuntu 13.04 following this tutorial: http://blog.neutrino.es/2013/howto-properly-activate-trim-for-your-ssd-on-linux-fstrim-lvm-and-dmcrypt/ See the ...
7
votes
3answers
13k views

How to check the life left in SSD or the medium's wear level?

We all know that SSDs have a limited predetermined life span. How do I check in Linux what the current health status of an SSD is? Most Google search results would ask you to look up S.M.A.R.T. ...
7
votes
4answers
3k views

Switch off syslog on laptop?

Is there any point in keeping logs on my laptop? This is not a server to debug problems via syslog. I occassionally want to look at dmesg | tail but that does not mean I need anything on disk. Wastes ...
7
votes
1answer
2k views

LVM + LUKS + SSD + Gentoo — making it all work together

I'm finding a lot of conflicting information out there, and as of yet haven't found anyone trying to pull together all of the components that I'm trying to do, so I'm hoping someone who understands ...
7
votes
1answer
2k views

What filesystem should I choose for an SSD? [duplicate]

I am going to set up a new Linux system on the SSD drive. Does the filesystem choice make a difference for them? Should I go with the default ext4, maybe try XFS, or does it just not matter?
6
votes
3answers
10k views

Persistent blockdev setra read ahead setting

I've got some SSDs mounted up on /dev/sda1 and /dev/sdb1 on a SLES 11 SP2 server, and I was able to tweak the read ahead setting with blockdev --setra: sudo blockdev --setra 4096 /dev/sda sudo ...
6
votes
3answers
764 views

Preload movie on RAM

My current computer is unable to run FullHD movies smoothly and I was already resigned to the idea, because it seemed a graphics card issue, mine not being powerful enought to do the work (which is ...
6
votes
1answer
1k views

Move /usr to SSD

I have an SSD and regular HDD drive in my laptop. The SSD drive is not used at all; it is not even being mounted. I am using Arch Linux. I'd like to start using the SSD, and from what I have read I ...
6
votes
1answer
4k views

Difference between 'sync' and 'async' mount options

What is the difference between sync and async mount options from the end-user point of view? Is file system mounted with one of these options works faster than if mounted with another one? Which ...
6
votes
2answers
929 views

Poor random read SSD performance on Linux

I recently got an Intel 320-series SSD, and I am having difficulty achieving the advertised 38K IOPS for random 4K reads. Both with fio and my own hacked-together program, I am seeing around 6K IOPS. ...
6
votes
1answer
6k views

How to configure a filesystem+LVM for effective usage of SSD?

ext4 is one of the filesystems recommended for using on SSDs (with a number of built-in techniques and advices how to tune it for better performance and wear-levelling of SSDs). I want to install a ...
6
votes
1answer
530 views

How to use an SSD for caching, so my hard disks can spin down?

I've got a file server with a bunch of disks running together in a BTRFS pool and want to add an SSD for caching. I'm not mainly after speeding up things, but want to catch the regular small accesses ...
5
votes
2answers
5k views

How to check drive temperature on Linux?

I have used of hdparm -n and smartctl -A but it always seem to be a "per drive" technique as a drive may answer for only one of these tools. So, is there a standard way to get the drive temperature ...
5
votes
2answers
983 views

Linux (3.4) SSD swap partition usage causes extreme latency - how to eliminate?

I'm running on 4G RAM with an extra 6G swap partition, SSD is a pretty decent SAMSUNG MZMPA128HMFU model. System responds very well to workloads when things stay in RAM, but as soon as things reach ...
5
votes
2answers
5k views

Benchmark ssd on linux: How to measure the same things as crystaldiskmark does in windows

I want to benchmark a ssd (possibly with encrypted filesystems) and compare it to benchmarks done by crystaldiskmark on windows. So how can I measure approximately the same things as ...
5
votes
1answer
907 views

btrfs and the discard mount option on an ssd

I can't seem to find an answer to this so I thought I would ask here: In /etc/fstab and when using the mount command in ext4 you would add the option discard to activate TRIM on an SSD. Similarly ...
5
votes
1answer
3k views

Installing pfSense firewall on an SSD

I was looking at creating a home firewall running pfSense (as I could not get IPCop to boot properly on my hardware). Doing a little research, however, I have some concerns with installing it onto an ...
4
votes
2answers
1k views

Is it OK to store /var/tmp on a SSD? [duplicate]

I have read that you should not store /tmp on a SSD, because the frequent writes will shorten the lifetime of the SSD. But what about /var/tmp? Is it reasonable for /var/tmp to be stored on a SSD? ...
4
votes
4answers
615 views

If I have an SSD and a hard disk in a system, can the SSD act as cache for the hard disk?

Say I have some partitions; one on a SATA drive and one on an SSD. I want to create a "virtual" hybrid disk. Is this possible?
4
votes
6answers
2k views

What about no swap?

I have a netbook with a very slow (especially on writes) SSD, would it be a good idea to go without swap? The way I see it is that code and unmodified pages will still be swapped (re-read) but I won't ...
4
votes
3answers
383 views

Hiding encryption key in unpartitioned free space of SSD

Anyone know what can happen if we use the unpartitioned space of an SSD hard drive to hide some data, what would happen? I have read that there are some SSD firmware using these blocks for recycling ...
4
votes
2answers
755 views

bcache on md or md on bcache

bcache allows one or more fast disk drives such as flash-based solid state drives (SSDs) to act as a cache for one or more slower hard disk drives. If I understand correctly, an SSD* could be ...
4
votes
1answer
370 views

fstrim and iostat

I have a new samsung ssd in my new notebook. I tuned up everything to avoid writings in the disk (firefox profiles and /var/log in memory), I'm using a ext4 fs with relatime and I use fstrim once a ...
4
votes
1answer
371 views

How to mount some folders on a different partition

I recently got an SSD for my computer. Therefore I reinstalled my system and mounted / on /dev/sda1 (which is a partition on the SSD). To protect the SSD, I managed to mount /tmp on the RAMdisk. ...
3
votes
7answers
1k views

How can I defragment my SSD on linux?

This page demonstrates that defragmentation is beneficial for SSDs. I suppose this type of defragmentation has to be trim-aware, so as to preserve the life time of the disk. How can I do that on ...
3
votes
3answers
2k views

Will formatting my drive TRIM my SSD?

Will a standard fresh linux (Ubuntu 11.10 to be exact) install and drive re-format (full) successfully TRIM my SSD, or do I need to do something extra? I know that ext4 will TRIM blocks on erase ...
3
votes
2answers
506 views

LVM with SSD and SATA hard disks

Is it possible to create LVM partitions for both SSD and SATA hard disks? I mean if there isn't any conflicts.
3
votes
2answers
7k views

How to enable SSD TRIM support on Fedora 17?

I used to install Linux on HDD. It's easy. But now I have a SSD, and I want to install Fedora 17 on it. What should I do to make Fedora 17 issue TRIM commands to the SSD?
3
votes
1answer
577 views

Can't enable TRIM on SSD

I can't enable TRIM on my newly-installed SSD. Ubuntu Server 12.04, Linux 3.11.0-15-generic. I turned TRIM on through discard setting in /etc/fstab. Also TRIM doesn't work with fstrim command. Here ...
3
votes
2answers
661 views

SSD as a read cache for FREQUENTLY read data

I'm looking for ways to make use of an SSD to speed up my system. In “Linux equivalent to ReadyBoost?” (and the research that triggered for me) I've learned about bcache, dm-cache and EnhanceIO. All ...
3
votes
3answers
10k views

partitioning using 2 hard disks (SSD and non-SSD) in linux [closed]

I have the following free spaces on 2 disks: SSD - 240G (sda) non-SSD - 240G (sdb) I understand that I should use SSD to install packages and non-SSD just for storing data. What's the best ...
3
votes
1answer
620 views

Possible issues with SSD SATA3 drive

While investigating the issue with my SATA3 SSD drive being recognized as SATA2 (for some reason had to change SATA ports to fix it) I noticed the following messages when I run: $ dmesg | grep ...
3
votes
3answers
445 views

Best way to benchmark different encryption solutions on my system

I want to compare different encryption solutions for encrypting my system, possibly different solutions for different parts of the system such as /usr or /home. In particular I look at dm-crypt ...
3
votes
2answers
495 views

Upgrading SSD Capacity - Clone Drive

I currently have a 60GB SSD that I have as my OS drive for Windows 7 partition and Fedora17 partition. Most data is stored on my 500GB HDD. I have upgraded to a 120GB drive, and want to clone the ...
3
votes
1answer
2k views

Using LVM with SSD and SATA drives

I saw in this question that it is possible to place both a SSD and a standard SATA hard drive into a single LVM volume group (VG). How does this affect performance? Is there a way to force the OS ...
3
votes
2answers
2k views

Optimal SSD configuration

I am thinking about buying an SSD for my Debian system. However, because I don't know what is the optimal arrangement (i.e. what goes on the SSD), I am not sure what is the optimal size. Obviously I ...
3
votes
0answers
56 views

Discover what is cached by dm-cache

I am using dm-cache successfully for quite a while now. Now I would like to know which files are being currently in the cache. I understand that dm-cache works with blocks, not files, but since there ...
3
votes
0answers
73 views

adding encrypted /home in LVM/LUKS

I installed a new (debian) system to an SSD device. After standard install I want to mount /home on the internal HDD. To be able to ask the question, some details: On install I (manually) generated ...
3
votes
0answers
31 views

Determine whether TRIM commands are being sent [duplicate]

I've configured multiple SSDs in a RAID-0 array in AHCI mode. I'd like to determine whether TRIM commands are being sent to the disks. Is there a way to monitor these commands in the kernel somewhere? ...
3
votes
2answers
280 views

How to dual boot Linux and Windows from small boot drive?

I am a Linux newbie, and I am trying to dual boot Linux Mint with Windows 7. Right now, Windows 7 boots from a small SSD, which has little extra room on it. Is there a way to set up a dual boot where ...
2
votes
3answers
137 views

Low level disk i/o on linux

Can a user level program do page level or block level I/O on SSDs? I've looked at disk devices, but am unsure if they provide this as they work only if the partition has a file system. UPDATE #1 I ...
2
votes
2answers
2k views

Installing Debian on an SSD

Does the Debian installer work out of the box for SSDs? I.e. I heard that you need to align the partitions to 32bit virtual clusters (is it actually true?). Are there any other things I need to take ...
2
votes
2answers
152 views

Why I have two /dev/sdx entries with a single disk?

In my laptop (running Linux) I have only one SSD, connected to the SATA3 port. Why I have two sdx entries in /dev directory? In particular I see /dev/sda and /dev/sdb, and /dev/sda is the SSD: # ...
2
votes
2answers
689 views

mbcache documentation

I want to experiment with mbcache kernel module, but I'm having trouble finding the documentation for it. If I understood correctly, mbcache allows the use of a fast SSD disk to act as a transparent ...