search for: wear

Hello! I'm using a CompactFlash as storage device. Since those CF cards only have limited write cycles (CF does wear-levelling by itself, but you don't want to write too many timet so the card) i was wondering by what a factor the journaling of ext3 increases the write accesses to the CompactFlash compared to ext2. Thanks a lot already for your help! Sincerely Chris Braun

...nding covariates. Maybe you have some advice for me, although this problem might only be 70% R and 30% statistically-related. Here's a detailled explanation: SITUATION & OBJECTIVE: I want to analyze the effect of environmental effects (i.e. temperature and humidity) on the lifetime of some wear-parts. The study should be conducted on a yearly basis, meaning that I have collected empirical data on every wearpart at the end of every year. DATA: I have collected the following data: - Status of the wear-part: Equals "0" if part is still alive, equals "1" if part has &quot...

...> > Does this mean that devices such as the samsung Flash SSD (part # > MCAQE32G5APP-0XA00) and the Supertalent Flashdrives are less reliable > than the HD equivalents. (since reliability is supposed to be their > biggest selling points)? What it means is that Flash memory cells wear out after a large number of read/write cycles, but not nearly as large as hard drives: http://en.wikipedia.org/wiki/Flash_rom#Limitations . So using Flash in place of RAM, even when high speed isn't important, can wear out the Flash - it will probably wear out even before HDs, which live less l...

...rite cycles are an issue here, though I can''t find any number in their spec. Why do I think it might be a bad idea: L2ARC is quite static in comparison with ZIL and L2ARC takes all the place it can get. But if 90% of the device are nearly statically allocated, the devices possibilities for wear-leveling are very restricted. If the ZIL is heavily used, the same 10% of the device get written over and over again, reducing the life span by 90%. Is there some fundamental flaw in this line of thought? Thanks, Arne

.../sdd 00000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff |................| * df99e6000 What''s a good way to test what state they get erased to from a TRIM operation? Can btrfs detect the erase state and pad unused space in filesystem writes with the same value so as to reduce SSD wear? Regards, Martin -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

Hi! With 3.2-rc4 (probably earlier), Ext4 seems to remember what areas it trimmed: merkaba:~> fstrim -v /boot /boot: 224657408 bytes were trimmed merkaba:~> fstrim -v /boot /boot: 0 bytes were trimmed But BTRFS does not: merkaba:~> fstrim -v / /: 4431613952 bytes were trimmed merkaba:~> fstrim -v / /: 4341846016 bytes were trimmed Is it planned to add this feature to BTRFS

..., i try to create a openWRT Samba 4.3 package and stumbled across the fact that samba 4.3 will create those message socks inside the private-dir. That results in creating entries inside /etc/samba/msg.sock. On openWRT /var is a tempFS in ram, so anything there is not a problem regarding nvram and wear leveling. Yet the root uses a jffs2 overlay. So while those message socks have no size, jffs2 still needs to write the dir table, since they survive a reboot. I'm now wondering how frequently those sock entries are created/deleted while running samba? In my tests the msg.sock folder kept growi...

I''m looking to try BTRFS on a SSD, and I would like to know what SSD optimizations it applies. Is there a comprehensive list of what ssd mount option does? How are the blocks and metadata arranged? Are there options available comparable to ext2/ext3 to help reduce wear and improve performance? Specifically, on ext2 (journal means more writes, so I don''t use ext3 on SSDs, since fsck typically only takes a few seconds when access time is < 100us), I usually apply the -b 4096 -E stripe-width = (erase_block/4096) parameters to mkfs in order to reduce...

...nWRT Samba 4.3 package and stumbled across the fact > that samba 4.3 will create those message socks inside the private-dir. That > results in creating entries inside /etc/samba/msg.sock. > > On openWRT /var is a tempFS in ram, so anything there is not a problem > regarding nvram and wear leveling. Yet the root uses a jffs2 overlay. So > while those message socks have no size, jffs2 still needs to write the dir > table, since they survive a reboot. > > I'm now wondering how frequently those sock entries are created/deleted > while running samba? In my tests the ms...

...nd the CF card is permanently sealed inside your device, for example), then you might want to consider disabling barriers so you're no longer forcing synchronous cache flush commands to be sent to your CF card. This trades off power failure safety versus increased performance and decreased card wear --- but if you don't need power failure safety, then it might be a good tradeoff. And if you *do* need power fail protection, then it's a good thing to test whether your hardware will actually provide it, so you don't find out the hard way that you're paying the cost of decreased p...

Well, the first day was interesting. We a variety of questions from why do we do this, what's going on with RH, how come this is the first I've heard of you. And hundreds more. The good thing is that we've recieve a very positive response from everyone that visited our booth. Such a positive response that all our CentOS CD's are gone, and most of the cAos CD's are gone, and

...wing options: /dev/disk/by-uuid/09a04c01-64c6-4600-9e22-525667bda3e3 on / type ext4 (rw,noatime,user_xattr,barrier=1,data=ordered) # dumpe2fs /dev/sda1 http://paste.debian.net/hidden/e3f81f11/ Are there kernel options to avoid synchronous disk writes? As suggested here: http://www.pcengines.ch/cfwear.htm Is there a list of other kernel options I can optimise to limit any cf wear? The devices don't use Kind regards Jelle de Jong -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iJwEAQECAAYFAlQ1ZhgACgkQ1WclBW9j5HmulgP9Fayd7V9t7bRgLo6NmjDVZoDM f+kH54/EnjsRfoKYYZDSO38WlwBWqJ1...

...a04c01-64c6-4600-9e22-525667bda3e3 on / type ext4 > (rw,noatime,user_xattr,barrier=1,data=ordered) > > # dumpe2fs /dev/sda1 > http://paste.debian.net/hidden/e3f81f11/ > > Are there kernel options to avoid synchronous disk writes? As > suggested here: http://www.pcengines.ch/cfwear.htm If you increase the journal commit interval (e.g. 30s) you can reduce the number of times a block needs to be written to the journal. The drawback is that you also increase the amount of un-sync'd metadata that would be lost in case of a crash. This usually means the data would also be l...

...d stumbled across the fact > > that samba 4.3 will create those message socks inside the private-dir. That > > results in creating entries inside /etc/samba/msg.sock. > > > > On openWRT /var is a tempFS in ram, so anything there is not a problem > > regarding nvram and wear leveling. Yet the root uses a jffs2 overlay. So > > while those message socks have no size, jffs2 still needs to write the dir > > table, since they survive a reboot. > > > > I'm now wondering how frequently those sock entries are created/deleted > > while running...

Hi We have a number offices accommodating 4-6 people each hence it is very important for PBX to be fanless and silent. We have been looking at using IDE flash disks also called DOM. The performance tests we have done so far satisfy our requirements, however we are concerned with DOM durability. We have installed debian and vanilla asterisk on 1GB DOM. All seems to work fine at the moment however

On Oct 16, 2014, at 10:25 AM, Bodo Thiesen <bothie@gmx.de> wrote: > * Andreas Dilger <adilger@dilger.ca> hat geschrieben: > >> You can see in the ext4 superblock the amount of data that has been >> written to a filesystem over its lifetime: >> >> Note that this number isn't wholly accurate, but rather a guideline. > > Is is more like a

Has anyone installed a high I/O application such as an email server on SSD drives? Was thinking about doing two SSD's in RAID1. It would solve my I/O latency issues but I have heard that SSD's wear out quickly in high I/O situations? Something like each memory location only has X many writes before its done. Just wandering if anyone has tested it and if newer SSD's are better about this?

...tly overestimates how long it will take, but is generally pretty close. For SSD's it can be way off. It says 8 minutes for my SSD, but the command returns in 5 seconds and the SSD spits back all zeros. Secure erase is really the only thing to use on SSDs. Writing a pile of zeros just increases wear (minor negative) but also doesn't actually set the cells to the state required to accept a new write, so you've just added a lot more work for the SSD's garbage collector and wear leveling, so it's going to be slower than before you did the zeroing. Secure erase on an SSD erases the...

* Andreas Dilger <adilger@dilger.ca> hat geschrieben: > You can see in the ext4 superblock the amount of data that has been > written to a filesystem over its lifetime: > > Note that this number isn't wholly accurate, but rather a guideline. Is is more like a completely bogus value at best: # LANG=C df -h / | grep root /dev/root 3.7T 3.6T 73G 99% / # grep [0-9]

I'm writing a program that will tell me whether I should wear a coat, so I'd like to be able to download daily weather forecasts and daily reports of recent past weather conditions. The NOAA has very promising tabular forecasts (http://forecast.weather.gov/MapClick.php?CityName=Ithaca&state=NY&site=BGM&textField1=42.4422&textField2=-76.50...