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OCZ Wants To Cache Your HDD With an SSD
sl4shd0rk writes "OCZ is coming out with Synapse Cache; an SSD cache for your hard drive. The SSD runs software that copies data into the cache from your hard drive as you work with it. The data sits on the SSD until it gets less activity and gets flushed to the hard disk. Aside from boosting your IOPS to 10k/75k (read/write), the SSD also supports AES encryption, SMART and TRIM."
They need to make the controller logic bullet proof, Seagate had quiet some problems with their hybrid disks
Exactly! ....In the same way that a meatball is a golf ball for those playing the game of spaghetti.
Well.. maybe. Or Maybe not. But Definitely not sort of.
Intel is doing the very same thing on their most recent "enthusiast" desktop chipsets.
For systems using the Linux kernel, there are software implementations of the very same block-level-caching-concept available - one I stumbled over is http://bcache.evilpiepirate.org/
:%s/Open Source/Free Software/g
YTARY!
No. The problem with caching in RAM is that it is volatile so if the power fails you'll lose the changes. Where this SSD helps is in providing a speed boost over a magnetic hard drive but without the volatility of RAM. The RAM cache will still be used to provide a further speed boost, but when a program issues an fsync to make sure that all the data held in the RAM cache is flushed to a physical disc, it will be the SSD that is picking up the slack.
For a read heavy environment with lots of RAM that is hardly ever switched off then probably not. For more general applications then it should provide a healthy speed boost without the cost of going all SSD.
That's simultaneously the best and least sensical analogy I've read on Slashdot in a long time. Kudos.
It's better to vote for what you want and not get it than to vote for what you don't want and get it.
- E. Debs
Quick Google says:
64GB SSD = $86
64GB RAM = $2000
Not sure I'm feeling the love for this concept. On the reads, sure. Nice idea. Writes however, not feeling the love. For whatever the reasons, PC hardware can lock up (CPU, video, motherboard, RAM etc) or because of buggy device drivers on the OS. In any event, how well can this device recover from a dirty-cache shutdown? What happens if the device just dies? Will I still be able to mount the HDD and recover data? It would be interesting to see how a journaling file system handles the abstraction of one volume read/written between two different drives. Were not talking about RAID5 here where you at least have parity data to recover from.
Life is not for the lazy.
I mean did you know many people have laptops that can take a 12.5mm tall HDD? But most people only buy a 9mm drive?
So it would be nice if OCZ (or another manufacturer) could make a very thin (3mm) card that would piggyback on top of the HDD. It would also have to a SATA drive connector to attach it to the motherboard and then a loop through cable to attach to the drive. In this way the end user could add a SSD cache to their existing laptop!
Is this feasible or am I missing something?
I use all of 16 gb of ram as an advanced home user doing video editing (by no means am I a pro).
That said, I use spinning disks for the video work because I amd rewriting blocks all the time with scratch and render files and while an SSD is faster, it's not enough to make up for the killing of the drive in short order (which I've already done once).
-nB
whois gawk date unzip strip find touch finger mount join nice man top fsck grep eject more yes exit umount sleep dump
Bravo sir.
This! Yes!
The current trend in flash process size reduction is to trade off erase endurance for the additional area shrinkage in pretty much a linear fashion.
So while the smaller tech allows for larger capacity drives in the same form factor, for two drives of equal capacity, equal over-provisioning, but different process sizes, you are much better off (in terms of erase endurance) with the larger process size.
I believe the latest shrink cut the erase endurance by approximately half, while approximately doubling density. At some limit you end up with exactly 1 erase cycle (and if doubling/halving is a trend, this wont take all that many process reductions) and you have to provision the vast majority of the drive (reserving all but fractions of a percentage!) for "wear leveling" in order to pretend that you have something other than a WORM drive.
"His name was James Damore."
Is it aware of the filesystem and keeps most accessed files, or just the most accessed blocks?
How is that an advantage? If I have e.g. a 5GB mail archive file which is my most accessed file, but I really only frequently access a few dozen MB of it which represent the most recently received mail, the performance will be much better if it will cache the frequently accessed blocks only and then use the rest of the SSD to cache other recently accessed blocks than if it uses up half the SSD to cache the whole mail archive even though I haven't accessed 7/8ths of it in the last two years.
I am very satisfied with increased performance from the drive
It's just your imagination. Check out these benchmarks, or compare it to even more recent standard hard drives.
It's hard to imagine how bad Seagate must have been with the design of a 3-1/2" drive that includes flash memory cache when it is regularly beaten in benchmarks by standard 2-1/2" drives (e.g., WD Scorpio Black) and trounced by other 3-1/2" drives. Since it costs a lot more (5x as expensive per GB as the WD Caviar Green), it's about the biggest loser ever made.
Prepare to have your mind unboggled:
For most people, the OS has been fast enough for the last decade. Boot times happen once per day at the most, programs launch once or twice per day and reside in large amounts of fast RAM. Even games reside just fine in 12GB of DDR3 and run like a champ on mid grade video cards. Where the speed breaks down for home users is Photos and Video. Everybody and their mom has digital photo and video equipment that fits in a purse or pocket.
It's working with these files where the SSD shines. Forget OS caching. We want media files _initially_ read from disk to be FAST. I want to transfer 24GB of hi res images to my pc and build a Lightroom catalog all in 2 minutes so I can work on them.. (I'm still waiting.). I want hd video to load and take edits without a pausing every 3 seconds while the disk spins. Storage AND Caching for these types of apps is great on an SSD. I certainly don't want windows contaminating my sacred SSD with it's super high, low ROI IOPS.
Operator, give me the number for 911!
Well according to this answer by a developer you CAN use an SSD for readyboost, its just isn't as straight forward and you can't use the whole drive. personally I've been avoiding SSDs until they get the bugs out as the experience from my gamer customers (who spent waaaay more than i would have for top o' the line SSDs) is that Jeff Atwood at coding horror is correct that SSDs should be judged on a hot/crazy scale as while they are crazy fast the fail crazy often.
To me it isn't THAT they fail it is HOW they fail that has me avoiding them. With HDDs I can't remember the last time I had an HDD that failed without plenty of clear warnings something was up. Windows delayed write fails, or SMART errors, temp going nuts, there was ALWAYS a clear warning that there was trouble in HDD town. With both of the gamers there was NO WARNING with the SSDs, they just flipped the switch and....nothing. With the HDDs I was always able to get the data off before they bought the farm, minus a few bad sectors of course, but with the SSDs it was like they didn't exist, it was just...nothing.
so while using it as a cache (as long as the cache is ALWAYS backed up like Readyboost) sounds fine i really can't see recommending an SSD until they get the bugs out. you would have to spend all your time running back ups or RAIDing the drive constantly to remove the risk, and that is just more trouble than its worth. Besides with Superfetch and Readyboost if you have a large amount of RAM (and what geek don't right? hell even my netbook is gonna have 6Gb on it) then everything you use often is already preloaded into RAM so unless you boot daily i doubt you'd see much difference, as nothing yet beats RAM speed.
ACs don't waste your time replying, your posts are never seen by me.
It depends entirely on the use scenario. Consider someone loads up a video game, and loads several files from a given folder. If the cache is aware of the filesystem, it will precache other content from that same folder, such as additional models, maps, and textures. When the game then wants to retrieve those files, they are ready to access, rather than having to pull them off the disk.
Too bad OCZ's Vertex 3 line does nothing but blue screen and cause system freezes as well as not being detected by the BIOS on occasion. 9 firmware revisions since we bought them, installed in multiple computers, and still no fix. They won't be getting my business. Doesn't matter how fast it is if you can't rely on it.
I use to be indecisive, but now I'm not so sure.
To me it isn't THAT they fail it is HOW they fail that has me avoiding them. With HDDs I can't remember the last time I had an HDD that failed without plenty of clear warnings something was up. Windows delayed write fails, or SMART errors, temp going nuts, there was ALWAYS a clear warning that there was trouble in HDD town. With both of the gamers there was NO WARNING with the SSDs, they just flipped the switch and....nothing. With the HDDs I was always able to get the data off before they bought the farm, minus a few bad sectors of course, but with the SSDs it was like they didn't exist, it was just...nothing.
Storage failures are nothing new... Google claims most HDD failures don't show any signs on SMART before going off. Add to this the fact that anyone not running with a bootable up-to-date backup (all OSs have cheap or free backup tools that create bootable backups) is asking for trouble. I've had HDDs fail without any warning (mostly on corporate systems). I've also had systems stolen (laptop), and the up-to-date backup was a life (and work) saver.
I own 3 SSDs now that work well and have yet to fail (surprisingly 2 of them are OCZ also). Comprising about 3 total disk-years of service. However, if they do, I just boot from my firewire backup drive, sync dropbox, git and IMAP and I would very likely have lost no work at all.
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That's not how Mark Russinovich describes it here.
"After the ReadyBoost service initializes caching, the Ecache.sys device driver intercepts all reads and writes to local hard disk volumes (C:\, for example), and copies any data being written into the caching file that the service created."
Do you have a source more authoritative than a blinking LED ?