From: Bakul Shah <bakul@iitbombay.org>
To: Dan Cross <crossd@gmail.com>
Cc: TUHS main list <tuhs@minnie.tuhs.org>
Subject: Re: [TUHS] FreeBSD behind the times? (was: Favorite unix design principles?)
Date: Fri, 5 Feb 2021 19:01:48 -0800 [thread overview]
Message-ID: <0076DB2B-48BC-45D3-8278-3D8528431E87@iitbombay.org> (raw)
In-Reply-To: <CAEoi9W7ZYojXNJYcUo5pw2+v1kApAz1MA5qGW6+EQkK=8nDAxA@mail.gmail.com>
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> On Feb 5, 2021, at 6:06 PM, Dan Cross <crossd@gmail.com> wrote:
>
> On Fri, Feb 5, 2021 at 7:04 PM Bakul Shah <bakul@iitbombay.org <mailto:bakul@iitbombay.org>> wrote:
>
> And you can keep track of mapped pages and read/write from them if
> necessary even if you have a separate cache for any compressed pages.
>
> In essence you pass the ownership of a page's data from a compressed
> page cache to the mapped page. Just like in processor cache coherence
> algorithms there is one source of truth: the current owner of a cached
> unit (line or page or whatever). In other words, the you see via mmap(2)
> will be the exact same page you will see via read(2). Not having actually
> tried this I may have missed corner cases + any practical considerations
> complicating things but *conceptually* this doesn't seem hard.
>
> In essence, that's what the merged page/buffer cache is all about: file IO (read/write) operations are satisfied from the same memory cache that backs up VM objects. I agree that conceptually it's not that complex; but that's not what ZFS does.
Good that we agree on that at least! This is why it would be good to hear from Bonwick/Moore.
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next prev parent reply other threads:[~2021-02-06 3:02 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-25 11:10 [TUHS] Favorite unix design principles? Tyler Adams
2021-01-25 12:32 ` Steve Nickolas
2021-01-26 2:06 ` M Douglas McIlroy
2021-01-26 2:53 ` Steve Nickolas
2021-01-26 10:22 ` Tyler Adams
2021-01-26 12:26 ` John P. Linderman
2021-01-26 15:23 ` Clem Cole
2021-01-26 16:00 ` Niklas Karlsson
2021-01-26 16:13 ` Adam Thornton
[not found] ` <CAKH6PiXKjksEpQOMMMQTbcsMvX2thz3WzqjoRWJAsXnZ4Eq_iQ@mail.gmail.com>
2021-01-30 19:01 ` Tyler Adams
2021-01-30 19:50 ` Jon Steinhart
2021-01-30 20:06 ` Tyler Adams
2021-01-30 21:28 ` Clem Cole
2021-01-30 21:42 ` Dave Horsfall
2021-01-30 21:45 ` Tyler Adams
2021-01-30 22:31 ` Larry McVoy
2021-01-30 22:28 ` Larry McVoy
2021-01-30 23:11 ` [TUHS] FreeBSD behind the times? (was: Favorite unix design principles?) Greg 'groggy' Lehey
2021-01-30 23:17 ` Larry McVoy
2021-01-30 23:22 ` Warner Losh
2021-01-30 23:31 ` [TUHS] [SPAM] " Larry McVoy
2021-01-30 23:37 ` Jon Steinhart
2021-01-30 23:54 ` Larry McVoy
2021-01-31 12:23 ` [TUHS] [SPAM] Re: FreeBSD behind the times? Dermot Tynan
2021-01-31 0:00 ` [TUHS] [SPAM] Re: FreeBSD behind the times? (was: Favorite unix design principles?) Bakul Shah
2021-02-09 2:15 ` [TUHS] " Will Senn
2021-02-09 2:16 ` Will Senn
2021-02-09 2:30 ` Greg 'groggy' Lehey
2021-01-31 0:39 ` Steve Nickolas
2021-01-31 1:47 ` Will Senn
2021-01-31 2:25 ` Larry McVoy
2021-01-31 2:52 ` Will Senn
2021-01-31 3:00 ` Larry McVoy
2021-01-31 3:06 ` Will Senn
2021-01-31 3:32 ` John Cowan
2021-02-04 5:43 ` Dave Horsfall
2021-02-04 6:10 ` Angus Robinson
2021-02-04 7:46 ` Andy Kosela
2021-02-04 22:25 ` Dave Horsfall
2021-02-04 15:45 ` Will Senn
2021-02-04 16:03 ` Henry Bent
2021-02-04 16:32 ` Dan Cross
2021-02-04 16:49 ` Will Senn
2021-02-04 17:46 ` Larry McVoy
2021-02-04 18:41 ` Bakul Shah
2021-02-04 22:28 ` George Michaelson
2021-02-04 22:41 ` Bakul Shah
2021-02-05 0:33 ` Larry McVoy
2021-02-05 5:17 ` Bakul Shah
2021-02-05 14:18 ` Larry McVoy
2021-02-05 18:16 ` Warner Losh
2021-02-05 18:21 ` ron minnich
2021-02-06 0:03 ` Bakul Shah
2021-02-06 2:06 ` Dan Cross
2021-02-06 3:01 ` Bakul Shah [this message]
2021-02-06 1:18 ` John Gilmore
2021-02-06 1:43 ` joe mcguckin
2021-02-06 1:55 ` Bakul Shah
2021-02-05 20:50 ` Dave Horsfall
2021-02-06 0:21 ` Brad Spencer
2021-02-06 2:22 ` Rico Pajarola
2021-02-06 2:55 ` Larry McVoy
2021-02-06 3:07 ` Will Senn
2021-02-27 8:54 ` Stuart Remphrey
2021-02-06 4:55 ` John Cowan
2021-02-04 7:46 ` Chris Torek
2021-02-04 15:47 ` Will Senn
2021-02-11 21:01 ` Angel M Alganza
2021-01-30 23:09 ` [TUHS] Favorite unix design principles? John Cowan
2021-01-30 23:22 ` Jon Steinhart
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