All of lore.kernel.org
 help / color / mirror / Atom feed
From: lijiang <lijiang@redhat.com>
To: John Ogness <john.ogness@linutronix.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
	Petr Mladek <pmladek@suse.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Andrea Parri <parri.andrea@gmail.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	kexec@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] printk: replace ringbuffer
Date: Thu, 6 Feb 2020 17:12:14 +0800	[thread overview]
Message-ID: <990f0076-7df2-c956-6181-fd222c1023f6@redhat.com> (raw)
In-Reply-To: <87sgjp9foj.fsf@linutronix.de>

> On 2020-02-05, lijiang <lijiang@redhat.com> wrote:
>> Do you have any suggestions about the size of CONFIG_LOG_* and
>> CONFIG_PRINTK_* options by default?
> 
> The new printk implementation consumes more than double the memory that
> the current printk implementation requires. This is because dictionaries
> and meta-data are now stored separately.
> 
> If the old defaults (LOG_BUF_SHIFT=17 LOG_CPU_MAX_BUF_SHIFT=12) were
> chosen because they are maximally acceptable defaults, then the defaults
> should be reduced by 1 so that the final size is "similar" to the
> current implementation.
> 
> If instead the defaults are left as-is, a machine with less than 64 CPUs
> will reserve 336KiB for printk information (128KiB text, 128KiB
> dictionary, 80KiB meta-data).
> 
> It might also be desirable to reduce the dictionary size (maybe 1/4 the
> size of text?). However, since the new printk implementation allows for
> non-intrusive dictionaries, we might see their usage increase and start
> to be as large as the messages themselves.
> 
> John Ogness
> 

Thanks for the explanation in detail.

Lianbo


  reply	other threads:[~2020-02-06  9:12 UTC|newest]

Thread overview: 58+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-28 16:19 [PATCH 0/2] printk: replace ringbuffer John Ogness
2020-01-28 16:19 ` [PATCH 1/2] printk: add lockless buffer John Ogness
2020-01-29  3:53   ` Steven Rostedt
2020-02-21 11:54   ` more barriers: " Petr Mladek
2020-02-27 12:04     ` John Ogness
2020-03-04 15:08       ` Petr Mladek
2020-03-13 10:13         ` John Ogness
2020-02-21 12:05   ` misc nits " Petr Mladek
2020-03-02 10:38     ` John Ogness
2020-03-02 12:17       ` Joe Perches
2020-03-02 12:32       ` Petr Mladek
2020-03-02 13:43         ` John Ogness
2020-03-03  9:47           ` Petr Mladek
2020-03-03 15:42             ` John Ogness
2020-03-04 10:09               ` Petr Mladek
2020-03-04  9:40           ` Petr Mladek
2020-01-28 16:19 ` [PATCH 2/2] printk: use the lockless ringbuffer John Ogness
2020-02-13  9:07   ` Sergey Senozhatsky
2020-02-13  9:42     ` John Ogness
2020-02-13 11:59       ` Sergey Senozhatsky
2020-02-13 22:36         ` John Ogness
2020-02-14  1:41           ` Sergey Senozhatsky
2020-02-14  2:09             ` Sergey Senozhatsky
2020-02-14  9:48             ` John Ogness
2020-02-14 13:29   ` lijiang
2020-02-14 13:50     ` John Ogness
2020-02-15  4:15       ` lijiang
2020-02-17 15:40       ` crashdump: " Petr Mladek
2020-02-17 16:14         ` John Ogness
2020-02-17 14:41   ` misc details: " Petr Mladek
2020-02-25 20:11     ` John Ogness
2020-02-26  9:54       ` Petr Mladek
2020-02-05  4:25 ` [PATCH 0/2] printk: replace ringbuffer lijiang
2020-02-05  4:42   ` Sergey Senozhatsky
2020-02-05  4:48   ` Sergey Senozhatsky
2020-02-05  5:02     ` Sergey Senozhatsky
2020-02-05  5:38       ` lijiang
2020-02-05  6:36         ` Sergey Senozhatsky
2020-02-05  9:00           ` John Ogness
2020-02-05  9:28             ` Sergey Senozhatsky
2020-02-05 10:19             ` lijiang
2020-02-05 16:12               ` John Ogness
2020-02-06  9:12                 ` lijiang [this message]
2020-02-13 13:07                 ` Petr Mladek
2020-02-14  1:07                   ` Sergey Senozhatsky
2020-02-05 11:07             ` Sergey Senozhatsky
2020-02-05 15:48               ` John Ogness
2020-02-05 19:29                 ` Joe Perches
2020-02-06  6:31                 ` Sergey Senozhatsky
2020-02-06  7:30                 ` lijiang
2020-02-07  1:40                 ` Steven Rostedt
2020-02-07  7:43                   ` John Ogness
2020-02-14 15:56                 ` Petr Mladek
2020-02-17 11:13                   ` John Ogness
2020-02-17 14:50                     ` Petr Mladek
2020-02-25 19:27                       ` John Ogness
2020-02-05  9:36           ` lijiang
2020-02-06  9:21 ` lijiang

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=990f0076-7df2-c956-6181-fd222c1023f6@redhat.com \
    --to=lijiang@redhat.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=john.ogness@linutronix.de \
    --cc=kexec@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=parri.andrea@gmail.com \
    --cc=peterz@infradead.org \
    --cc=pmladek@suse.com \
    --cc=rostedt@goodmis.org \
    --cc=sergey.senozhatsky.work@gmail.com \
    --cc=sergey.senozhatsky@gmail.com \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.