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From: Giacomo Tesio <giacomo@tesio.it>
Date: Mon, 15 Oct 2018 11:29:07 +0200
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To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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Subject: Re: [9fans] PDP11 (Was: Re: what heavy negativity!)
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Il giorno dom 14 ott 2018 alle ore 19:39 Ole-Hjalmar Kristensen
<ole.hjalmar.kristensen@gmail.com> ha scritto:
>
> OK, that makes sense. So it would not stop a client from for example first read an index block in a B-tree, wait for the result, and then issue read operations for all the data blocks in parallel.

If the client is the kernel that's true.
If the client is directly speaking 9P that's true again.

But if the client is a userspace program using pread/pwrite that
wouldn't work unless it fork a new process per each read as the
syscalls blocks.
Which is what fcp does, actually:
https://github.com/brho/plan9/blob/master/sys/src/cmd/fcp.c


Giacomo