:: Re: [DNG] strange effect on overwri…
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Author: Rich W
To: Radisson
CC: Eric via Dng
Subject: Re: [DNG] strange effect on overwrite

A blocksize of 1G seems extreme.
What is the optimal blocksize of the output device?


On Thu, Jun 23, 2022, 4:52 AM Radisson via Dng <dng@???> wrote:

> Hi list,
> i found a strange ext4 (?) effect.
> when i write to a disk:
> dd if=/dev/zero of=xx bs=1G count=1
> reports 2.6 GB (expected)
> doing again speed drops to 200MB.
> removing xx restores old speed.
> I ask the net and it seems that the effect is there
> since kernel 2.6. I found the explainations a bit confusing.
> does anyone know more ?
> note: i was analysing a performace issue for mysql and i am
> not sure if that problems matters outside tests.
> re
> rp
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