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I recently read that differences between disk page size in the partition vs flash storage can hurt write performance.

So, I checked the partition sizes on some database disks with parted and got

Output: Sector size (logical/physical): 512B/4096B which obviously shows a difference.

However, I'm not sure if changing the partition size would help here.

We are using GCP's zonal persistent ssd (not sure what the generic industry term is) and not a raw SSD.

Does the general advice on aligning SSD block sizes apply to "cloud persistent disks?"

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It doesn't really matter.

The SSD page size is invisible and inaccessible to you, and it might even change during the lifetime of your persistent disk when the underlying storage is upgraded or replaced.

In any event all your disk reads and writes are going over a network anyway before they reach the storage server and finally get written to physical media.

Overall, on a cloud provider this is rarely worth worrying about. You'd see very little difference in performance, and the SSD lifetime is something for the cloud provider to worry about, not you.

And finally, your disk partitions are already aligned to a multiple of the SSD page size anyway.

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  • So the parted result is basically irrelevant in this case? Commented Jan 8, 2019 at 17:13
  • It's completely irrelevant. You'll even see the same thing on your local SSD in your own computer. Commented Jan 8, 2019 at 17:13
  • Just so I understand correctly, you're saying the parted result is irrelevant for the SSD on my own computer? Commented Jan 8, 2019 at 17:14
  • The so-called logical vs physical sector size doesn't mean much on a SSD, as you know the actual page size is much larger than either one (e.g. 16KiB). Commented Jan 8, 2019 at 17:19
  • Oh, that makes sense. I don't want to occupy more of your time as I think you answered my question. Do you have any resources where I could learn more about this? Also, did I misunderstand the article I linked to? Thanks. Commented Jan 8, 2019 at 17:21

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