[HN Gopher] Acard ANS-9010B 5.25-inch SATA x1-to-6-slot DDR2 RAM...
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Acard ANS-9010B 5.25-inch SATA x1-to-6-slot DDR2 RAM Disk
(Deactivated)
Author : thunderbong
Score : 23 points
Date : 2023-03-11 17:47 UTC (5 hours ago)
(HTM) web link (www.scsi4me.com)
(TXT) w3m dump (www.scsi4me.com)
| 1MachineElf wrote:
| I have 4 of these each with 16GB ECC RAM. Used them as a ZFS
| cash. They run kinda hot.
| somat wrote:
| The more I think about it the less sense a ram disk makes, I will
| admit it, I have abused them in the past, once for battlefield3
| because the load times on my setup were awful and once for a
| company, they wanted a lookup using a specific database product
| that had no way to do in memory tables.
|
| But resorting to a ramdisk means you have failed. most of the
| time the page cache offers the semantics you actually want,
| memory quick access backed up by persistent storage. You are
| saying, I want a filesystem api with ram speed and are willing to
| jump through the hoops required, manually syncing your storage at
| startup and shutdown, to reach that specification.
| throwaway81523 wrote:
| > most of the time the page cache offers the semantics you
| actually want, memory quick access backed up by persistent
| storage.
|
| If you are thinking about a ram disk it is likely because you
| want guaranteed low latency. With a cache you get hosed by
| delays when pages are flushed. I remember having to run daemons
| just to keep caches warm by periodically accessing data that I
| might need later without having to wait for it.
| bombcar wrote:
| RAM disks had their heyday in the 32 bit era, where computers
| could be limited to 4GB of RAM but if you wanted to you could
| get a much larger RAMdisk.
| throwaway81523 wrote:
| There was a time when 1GB of memory cost maybe $50 but you had to
| pay a sizeable premium to buy a server capable of handling more
| than 4GB. Sites had racks full of 4GB servers acting as memcached
| boxes. It's a lot easier to buy servers that can hold 256gb or
| more of ram, so your expenditures are more balanced between ram
| and other stuff, and you are still using commodity ram.
| chx wrote:
| > There was a time when 1GB of memory cost maybe $50 but you
| had to pay a sizeable premium to buy a server capable of
| handling more than 4GB.
|
| Looking at the memory price timeline
| https://jcmit.net/memoryprice.htm it was middle 2007 when 1GB
| memory hit $50 (row 2007.33 it's a very big drop in $/memory as
| you can see in the second column). A contemporary server
| motherboard would be the Supermicro X7DCL
| https://www.supermicro.com/manuals/motherboard/5100/MNL-0957...
| with six slots of DDR2 memory capable of handling 48GB RAM
| https://ark.intel.com/content/www/us/en/ark/products/33142/i...
| but even with cheap memory it was easily doing 12-24GB RAM.
|
| Looking at it from another angle,
| https://github.com/memcached/memcached/wiki/ReleaseNotes150
| "Memcached was introduced in 2003" which is a bit after Socket
| 604 and looking at those boards
| https://www.supermicro.com/products/motherboard/archive/?mlg...
| it does not seem like at that era 8GB maximum would be uncommon
| (8GB instead of 4GB because we want to use cheaper than top
| modules), in fact very few motherboards top out at 8GB, most
| could do a lot more. This is to say, there doesn't seem to be a
| period of history where memcached existed but commodity servers
| handling more than 8GB didn't exist.
|
| Yet another angle, I upgraded from the Panasonic CF-Y5 to a
| ThinkPad T400s because the CF-Y5 topped out at 2GB and that was
| in 2009 (I checked my records, 2009 August 11) and so servers
| not handling vastly more is extremely unlikely. At this time
| the company I worked with certainly had dedicated memcached
| boxes yes, but a lot more than 4GB RAM, can't remember exactly
| how much.
|
| I would cautiously say you misremember your numbers.
| throwaway81523 wrote:
| > with six slots of DDR2 memory capable of handling 48GB RAM
|
| 1) that was a premium motherboard, 2) 16 ram sticks were way
| more expensive per GB than smaller sticks. I think you have
| the timeframe about right (2008?), but where I worked we had
| 1000s of servers built on PC motherboards (cheap) with 4
| slots holding 1GB each. 4GB sticks existed but cost a lot
| more per GB and were hard to find, and our motherboards
| needed some kind of bios change to use them. We did manage to
| upgrade a few machines to 16gb and they were useful.
| consp wrote:
| If you want a ramdisk maybe look into these:
| https://ddramdisk.store/2023/02/15/the-ddr4-pcie-x8-lady-suc...
|
| I'm not in anyway connected to this, found it after looking for
| something modern after seeing a YouTube video about old ramdisks.
| cm2187 wrote:
| Would it be better to user DDR3, or anything you can buy for
| cheap on ebay? You won't use the full speed of the RAM anyway,
| so why use those older RAM modules that would go to waste
| anyway.
| JoshTriplett wrote:
| I can understand why, historically, it made sense to have
| something that looks like a hardware disk but uses RAM. But
| today, what's the use case for this, versus just adding the RAM
| to the system directly and using a software RAM disk? That
| avoids the disk protocol entirely, and should provide
| substantially better performance.
| compsciphd wrote:
| I believe this is battery backed, so it doesn't lose data
| when powered off. With that said, mmap hard disk file would
| get similar performance (minus fsync overhead to the
| persistent disk backing store).
| 13of40 wrote:
| Any idea how this compares to enabling write caching on a
| drive or on your database layer, if you're using one? I
| mean other than the catastrophic effects of a sudden power
| outage.
| DominoTree wrote:
| I'd think the main benefit these days might be cost savings
| from using RAM that's a generation or two older, but in
| general I think the use case for these hardware RAM disks is
| probably pretty slim nowadays.
| 13of40 wrote:
| Didn't there used to be a version of this that was RAM plus a
| mechanical hard disk it would get dumped to when powered down?
| ("hybrid hard disk" seems to mean SSD+Mechanical now.)
| consp wrote:
| I don't know. Only ever heard about the OP's thing with
| compact flash. But since cf is IDE I guess you can use
| spinning rust as well.
| ChoGGi wrote:
| There's one for sale on eBay if you're looking to buy?
|
| https://www.ebay.com/itm/125610100927
| duskwuff wrote:
| "Data transfer rate up to 200MB/sec"
|
| So it's not even as fast as a modern SATA SSD. Oof.
| formerly_proven wrote:
| Depends on the modern SATA SSD, QLC SSDs are quite a bit
| slower than 200 MB/s for writing (something like a Samsung
| 870 QVO manages about 150 MB/s real-world, cheaper ones are
| probably even slower), so they're actually slower than
| current HDDs for sequential writes.
| IronWolve wrote:
| Interesting, before cheap ram disks maybe had a use case, but now
| motherboards have 2/3 m2's with raid options. Or even jbod ssd's
| for software style raid.
|
| Uses ddr2 and ram was expensive when it came out, so can see it
| wasn't super popular. But neat idea.
|
| https://techreport.com/review/16255/acards-ans-9010-serial-a...
| bcrl wrote:
| There's still a use-case for them. High performance high
| reliability persistent messaging is one such use case where
| SSDs do not have the required endurance. Solace builds their
| hardware messaging appliances with the Assured Delivery Blade
| that consists of an FPGA based board with supercap backed DRAM
| that dumps to flash on power failure and a couple of 10Gbps
| ports to mirror to another system. The end result is extremely
| low latency acknowledgement of non-volatile storage of
| persistent messages with unlimited endurance.
| IronWolve wrote:
| With that being a 5.25, year and brand I was thinking desktop
| usage. For enterprise, I'm sure theres always a need for
| some.
| gigel82 wrote:
| I went looking for something like this for NVMe drives and
| there's surprisingly little available. External (USB3) adapters
| for NVMe drives can be had for under $20, so I'm surprised there
| aren't internal 2.5'' / 3.5'' options available (there are PCIe
| cards, but on a mini-itx board there are no extra slots besides
| the GPU).
| upon_drumhead wrote:
| Why spend the money for a super fast direct pcie ssd and then
| pay more money to cripple it down to sata speeds when you could
| just buy a sata ssd or msata+adapter way cheaper?
| gigel82 wrote:
| I agree it's a pretty niche requirement. But I have 8x 1Tb
| NVMe drives after pulling them out of a server and nothing to
| use them for :)
| happycube wrote:
| Also it's a complex adapter, since it has to be a PCI-e host.
| Generally SATA->x (USB, SD card, etc) adapters can be done
| with much simpler app-specific microcontrollers with IP
| blocks sprinkled in.
| GordonS wrote:
| One reason is SATA SSDs are more of expensive than their m2
| counterparts - at least they were here in the UK when I
| recently purchased an SSD.
|
| Another reason could be size - in a 5.25" form factor, you
| could potentially "stack" several m2 SSDs in blade-like
| fashion. I haven't seen such a thing though, and heat might
| be an issue.
| upon_drumhead wrote:
| 2.5" 2T Samsung ssd on Amazon is $135 and a 2T nvme is
| slightly cheaper at $125. That $10 in savings is going to
| totally be eaten in adapters though.
|
| So there are 5.25" multiple m2 adapters out there like
|
| https://www.icydock.com/goods.php?id=255
|
| That one would require a sas controller to connect to.
|
| You generally don't see a tighter system like blades due to
| needing a bifurcated pcie slot support, which at that point
| of server hardware, your are generally not using adapters
| like this.
| Dylan16807 wrote:
| That enclosure isn't m.2, that's 2.5" NVMe. Like a SATA
| drive but with more pins stuffed in the plug. Though I
| guess you could put extra adapters inside it.
|
| Is the ability to bifurcate a PCIe slot (and avoid extra
| controllers) that rare? That's a shame.
| upon_drumhead wrote:
| Whoops. I linked the wrong model. Middle of that page has
| a section on all the different options for the drive bay.
| A few that look very similar are m2 nvme.
|
| I have a https://www.supermicro.com/en/products/motherboa
| rd/X10DRH-iT and they don't support bifurcated pcie. It's
| a shame cause I've extended the life of the servers by
| using pcie adapters to add high speed io layers and I'm
| limited to one device per port. I'd love to double that
| density.
| Dylan16807 wrote:
| SATA SSDs are a little bit cheaper here.
|
| Hot swap bays are usually set up for 2.5" drives. You can
| fit 4-8 into a single 5.25" slot. But the ones designed for
| performance will prefer U.2 drives and hook them up to
| PCIe.
|
| https://www.icydock.com/goods.php?id=321
| m463 wrote:
| I think if you're doing LOTS of writes to something you don't
| care a lot about - a ramdisk might be a nice way to prevent you
| from killing your SSD.
|
| Say, most things you put in /var
|
| This particular unit might also work for a machine where you
| install a client OS on the main (ramdisk) HD and reboot, then
| wipe and do it again later.
| gruez wrote:
| >I think if you're doing LOTS of writes to something you don't
| care a lot about - a ramdisk might be a nice way to prevent you
| from killing your SSD.
|
| >Say, most things you put in /var
|
| Even a bottom of the barrel QLC SSD can handle 100GB of writes
| per day without problems. Therefore it's unlikely that moving
| stuff in /var (random log/temporary files) off the SSD is going
| to change its lifespan by much.
| cm2187 wrote:
| video editing?
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(page generated 2023-03-11 23:01 UTC)