Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1188190

Re: [PATCH v9 08/22] tracing: Add 'hist' event trigger command

Show all headers | View raw

Hi Tom,

On 2015/07/17 2:22, Tom Zanussi wrote:

> @@ -3782,6 +3785,32 @@ static const char readme_msg[] =
>  	"\t   To remove a trigger with a count:\n"
>  	"\t     echo '!<trigger>:0 > <system>/<event>/trigger\n"
>  	"\t   Filters can be ignored when removing a trigger.\n"
> +#ifdef CONFIG_HIST_TRIGGERS
> +	"      hist trigger\t- If set, event hits are aggregated into a hash table\n"
> +	"\t    Format: hist:keys=<field1>\n"
> +	"\t            [:size=#entries]\n"
> +	"\t            [if <filter>]\n\n"
> +	"\t    When a matching event is hit, an entry is added to a hash\n"
> +	"\t    table using the key named.  Keys correspond to fields in the\n"
> +	"\t    event's format description.  On an event hit, the value of a\n"
> +	"\t    sum called 'hitcount' is incremented, which is simply a count\n"
> +	"\t    of event hits.  Keys can be any field.\n\n"
> +	"\t    Reading the 'hist' file for the event will dump the hash\n"
> +	"\t    table in its entirety to stdout.  Each printed hash table\n"
> +	"\t    entry is a simple list of the keys and values comprising the\n"
> +	"\t    entry; keys are printed first and are delineated by curly\n"
> +	"\t    braces, and are followed by the set of value fields for the\n"
> +	"\t    entry.  Numeric fields are displayed as base-10 integers.\n"
> +	"\t    By default, the size of the hash table is 2048 entries.  The\n"
> +	"\t    'size' param can be used to specify more or fewer than that.\n"
> +	"\t    The units are in terms of hashtable entries - if a run uses\n"
> +	"\t    more entries than specified, the results will show the number\n"
> +	"\t    of 'drops', the number of hits that were ignored.  The size\n"
> +	"\t    should be a power of 2 between 128 and 131072 (any non-\n"
> +	"\t    power-of-2 number specified will be rounded up).\n\n"
> +	"\t    The entries are sorted by 'hitcount' and the sort order is\n"
> +	"\t    'ascending'.\n\n"


Hmm, this seems too much about implementation of histogram. Could you shorten this
to be a half ?


Thank you,


-- 
Masami HIRAMATSU
Linux Technology Research Center, System Productivity Research Dept.
Center for Technology Innovation - Systems Engineering
Hitachi, Ltd., Research & Development Group
E-mail: masami.hiramatsu.pt@hitachi.com
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v9 00/22] tracing: 'hist' triggers Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  [PATCH v9 09/22] tracing: Add hist trigger support for multiple values ('vals=' param) Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  [PATCH v9 01/22] tracing: Update cond flag when enabling or disabling a trigger Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  [PATCH v9 15/22] tracing: Add hist trigger 'sym' and 'sym-offset' modifiers Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  [PATCH v9 16/22] tracing: Add hist trigger 'execname' modifier Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  [PATCH v9 11/22] tracing: Add hist trigger support for user-defined sorting ('sort=' param) Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  [PATCH v9 12/22] tracing: Add hist trigger support for pausing and continuing a trace Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
    Re: [PATCH v9 12/22] tracing: Add hist trigger support for pausing  and continuing a trace Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> - 2015-07-22 10:30 +0200
  [PATCH v9 08/22] tracing: Add 'hist' event trigger command Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
    Re: [PATCH v9 08/22] tracing: Add 'hist' event trigger command Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> - 2015-07-20 15:40 +0200
  [PATCH v9 14/22] tracing: Add hist trigger 'hex' modifier for displaying numeric fields Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  [PATCH v9 17/22] tracing: Add hist trigger 'syscall' modifier Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  [PATCH v9 04/22] tracing: Add event record param to trigger_ops.func() Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  [PATCH v9 05/22] tracing: Add get_syscall_name() Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
  Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Peter Zijlstra <peterz@infradead.org> - 2015-07-16 20:00 +0200
    Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 23:50 +0200
      Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Peter Zijlstra <peterz@infradead.org> - 2015-07-17 00:40 +0200
        Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-17 04:00 +0200
  Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Peter Zijlstra <peterz@infradead.org> - 2015-07-16 20:10 +0200
    Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 23:40 +0200

csiph-web