IDE DOM or CFCard for disk emulator
So I’m trying to understand which is better, forgetting you can quickly remove a CF Card vs the IDE DOM. I’m just about done with my Lisa 2/10 and am using an XProfile drive replacement for the widget drive. With the way the XProfile is mounted both an IDE DOM and CF Card are easy to swap in and out but I’m worried that in the long run LisaOS does a lot of writing of state to the disk. For the occasional MacWorks use to run Macintosh software on the Lisa, I will use a CF Card. Does one have a different read/write duty cycle so it will last longer? Or are they really these days just the same thing in a different package/interface? Thanks, Corey corey cohen uǝɥoɔ ʎǝɹoɔ
On Jan 10, 2018, at 05:22, corey cohen via vcf-midatlantic <vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
So I’m trying to understand which is better, forgetting you can quickly remove a CF Card vs the IDE DOM.
I’m just about done with my Lisa 2/10 and am using an XProfile drive replacement for the widget drive. With the way the XProfile is mounted both an IDE DOM and CF Card are easy to swap in and out but I’m worried that in the long run LisaOS does a lot of writing of state to the disk. For the occasional MacWorks use to run Macintosh software on the Lisa, I will use a CF Card.
Does one have a different read/write duty cycle so it will last longer? Or are they really these days just the same thing in a different package/interface?
You can find "industrial" CF cards that are meant for disk use. They're often SLC, so they cost more, but their durability and retention is way better than MLC. Other than that, it's luck of the draw; I'm sure there are plenty of crappy DOMs that are just as bad as bad photo CF cards. The general issue will be reliability, which depends on the type of cell (SLC vs MLC) and the wear leveling algorithm. If you want to make it last longest, just try not to churn on it too much. When I put a Unix system on CF for embedded machines or routers, I typically mount everything read-only and mount /var and anything else that gets constant reads as a RAM disk, then sync contents to persistent storage every hour or so. My home router has been running on a 4 GB CF card like that for many years, and the last one ran on a 64 MB one for close to a decade. - Dave
Industrial DOMs typically have better IDE emulation, in my experience. Dave is right, there are plenty of crappy DOMs out there -- I only buy trusted brands from sellers known not to provide fakes. Typically I stick to SiliconDisk (now WD I think), M-Systems, PQI, Axiomtek, Smart Technologies, etc. Definitely go with an industrial CF card if you go for CF. All of the reputable industrial suppliers will provide a data sheet spec'ing write endurance. Many consumer suppliers do not, in which case you get to assume it's something horrible like 3000 (yes, three *thousand*) rewrites. Thanks, Jonathan On Wed, Jan 10, 2018 at 7:40 AM, David Riley via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
On Jan 10, 2018, at 05:22, corey cohen via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
So I’m trying to understand which is better, forgetting you can quickly
remove a CF Card vs the IDE DOM.
I’m just about done with my Lisa 2/10 and am using an XProfile drive
replacement for the widget drive. With the way the XProfile is mounted both an IDE DOM and CF Card are easy to swap in and out but I’m worried that in the long run LisaOS does a lot of writing of state to the disk. For the occasional MacWorks use to run Macintosh software on the Lisa, I will use a CF Card.
Does one have a different read/write duty cycle so it will last longer?
Or are they really these days just the same thing in a different package/interface?
You can find "industrial" CF cards that are meant for disk use. They're often SLC, so they cost more, but their durability and retention is way better than MLC.
Other than that, it's luck of the draw; I'm sure there are plenty of crappy DOMs that are just as bad as bad photo CF cards. The general issue will be reliability, which depends on the type of cell (SLC vs MLC) and the wear leveling algorithm.
If you want to make it last longest, just try not to churn on it too much. When I put a Unix system on CF for embedded machines or routers, I typically mount everything read-only and mount /var and anything else that gets constant reads as a RAM disk, then sync contents to persistent storage every hour or so. My home router has been running on a 4 GB CF card like that for many years, and the last one ran on a 64 MB one for close to a decade.
- Dave
On Jan 10, 2018, at 2:32 PM, systems_glitch via vcf-midatlantic <vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
Industrial DOMs typically have better IDE emulation, in my experience. Dave is right, there are plenty of crappy DOMs out there -- I only buy trusted brands from sellers known not to provide fakes. Typically I stick to SiliconDisk (now WD I think), M-Systems, PQI, Axiomtek, Smart Technologies, etc.
Yeah, I've come across some crappy CF cards with bad IDE emulation that OpenBSD choked on a bit, mostly at boot time. I actually ended up moving to a SATA->CF converter on my current router, which behaved better because it meshed well with the card's faults.
Definitely go with an industrial CF card if you go for CF. All of the reputable industrial suppliers will provide a data sheet spec'ing write endurance. Many consumer suppliers do not, in which case you get to assume it's something horrible like 3000 (yes, three *thousand*) rewrites.
It's worth noting that SiliconDisk (which is, yes, now owned by WD) also has industrial CF cards. I'm assuming it's probably very similar electronics to their DOM. - Dave
participants (3)
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corey cohen -
David Riley -
systems_glitch