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> Some workloads are write-intensive and some aren't. Did you read what I wrote? Do you mean delete-intensive?
by jcampbell1 13y ago
> Some workloads are write-intensive and some aren't.
Did you read what I wrote? Do you mean delete-intensive?
- wtallis 13y agoI don't think there's any truth to your notion that deletes are somehow worse for a solid state drive than other kinds of writes. Overwriting a sector has the same effect on longevity as erasing it and filling it up again, but in the latter case, you can use the ATA TRIM command to defer the flash block erase latency (which is significantly higher than the flash program latency). The only way in which deletes are "bad" is if you're comparing to a workload that fills the drive once and then moves on to fill a different drive - but that's not a fair comparison against doing all the writes to the same drive. Different workloads can somewhat affect how much write amplification results from the wear leveling, but the best-case there actually is to have no long-lived data on the drive, ie. lots of deletes.
- smoyer 13y agoI think he's assuming that since it's actually rewritten flash-memory bits that degrade, if you don't delete data, then you don't rewrite. So without deletes, all writes simply fill more of the drive and you shouldn't see degradation. Modern flash drives do indeed try to level the writes across all bits, but he's talking about work-loads that don't rewrite at all.
- sirclueless 13y agoI wouldn't call an application that writes once and never deletes anything on the hard drive a write-intensive workload. Filling up a SSD with write-once data means paying well over 50¢/GB for your writes, which isn't something you can do if you are "write-intensive" -- if you're writing 100x the capacity of the drive over its lifetime, then you are really write-intensive, at which point the distinction between delete-intensive and write-intensive is nearly nonexistent for obvious reasons.