From: gao xu <gaoxu2@honor.com>
To: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>, Jens Axboe <axboe@kernel.dk>,
"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
"surenb@google.com" <surenb@google.com>,
zhouxiaolong <zhouxiaolong9@honor.com>
Subject: RE: zram: Optimize LZ4 dictionary compression performance
Date: Wed, 11 Mar 2026 04:00:48 +0000 [thread overview]
Message-ID: <cfb89ffc52d649f39ec98b844efa8bd9@honor.com> (raw)
In-Reply-To: <aa-2nItXDdeDj4Xi@google.com>
>
> On (26/03/10 02:54), gao xu wrote:
> > + memcpy(zctx->cstrm, &drv->base_cstream,
> > + sizeof(*zctx->cstrm));
>
> Do we need to do this memcpy() every time?
memcpy is a replacement for LZ4_loadDict. LZ4_loadDict updates the LZ4 hash table using the dictionary. Furthermore, LZ4 also updates its hash table with the results of the previous compression. Therefore, to ensure the compression dictionary remains effective, we would need to reset the hash table every time, which would involve executing memcpy() or LZ4_loadDict(). (Please correct me if there's any misunderstanding here.)
> A nit: if it cannot fit on one line, then let's align sizeof(*zctx->cstrm) with "(".
Received, thank you.
next prev parent reply other threads:[~2026-03-11 4:00 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-10 2:54 zram: Optimize LZ4 dictionary compression performance gao xu
2026-03-10 5:39 ` Sergey Senozhatsky
2026-03-10 6:13 ` Sergey Senozhatsky
2026-03-10 6:22 ` Sergey Senozhatsky
2026-03-10 8:32 ` gao xu
2026-03-11 1:22 ` Sergey Senozhatsky
2026-03-11 2:55 ` gao xu
2026-03-10 6:15 ` Sergey Senozhatsky
2026-03-11 4:00 ` gao xu [this message]
2026-03-11 5:22 ` Sergey Senozhatsky
2026-03-11 1:25 ` Sergey Senozhatsky
2026-03-11 2:56 ` gao xu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=cfb89ffc52d649f39ec98b844efa8bd9@honor.com \
--to=gaoxu2@honor.com \
--cc=akpm@linux-foundation.org \
--cc=axboe@kernel.dk \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=minchan@kernel.org \
--cc=senozhatsky@chromium.org \
--cc=surenb@google.com \
--cc=zhouxiaolong9@honor.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox