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Re: write alignment matters?



    Date:        Fri, 24 Jun 2011 00:09:58 -0700
    From:        Erik Fair <fair%NetBSD.org@localhost>
    Message-ID:  <D4B3CB6F-ECBC-4DB6-97C2-031BE0D264B3%netbsd.org@localhost>

  | Oh, and as noted before, through the block interface, you could do
  | arbitrary (up to ... was it 64KB?

Just under that, the count arg on read/write was an int after all (on
a 16 bit system).  Negative counts make no sense, so 65535 was the max
possible, but if your I/O was 65535 detecting the difference between
"it worked" and "error" was non trivial.

  | Of course, if you want to talk about really slow I/O with massive
  | latency, let's talk about random access to DECtapes ...

In order to get a system booted, I ran (once or twice) with root
mounted (read only, naturally) from a 9-track tape.   Slow doesn't
begin to describe it, but it did work.

Michael van Elst <mlelstv%serpens.de@localhost> said:
  | Oh, I was talking about current NetBSD where block devices are a second
  | class citizen, soon to be abolished if someone finds enough round tuits. 

Yes, so it keeps being said.  It would truly be a pity to see that happen.

kre



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