DBA Tools:sp_whocpu

  • Comments posted to this topic are about the item DBA Tools: sp_whoCPU[/url]

    Hi All,

    Just a note to let you know that the issue with the TAB characters has been resolved, so you can just copy and paste the script if you would like to use it.

    Thanks

  • Thanks for the script.

    I've sucessfully run it and created the sp but when I run the sp itself in SS management studio (2005), I only get the colunm headers but no results.

    Am I missing something?

  • Hi,

    This is possible, if there is no activity on the server, during the 3 seconds period when the sp_whocpu calculates the cpu_delta.

    The spid that runs sp_whocpu is ignored.

    None of the sleeping processes which do not consume cpu will show either, so it is possible that at a certain moment you don't get any output.

    This is what differentiates sp_whocpu from sp_who2 for example. Running sp_who2 will show all processes, some with quite high cpu figures, when in fact they do not consume any resources at that moment in time.

    Cheers,

    Mircea

  • Outstanding.

    This makes perfect sense as it was on my DEV server which had open connections but may not have been processing anything. 🙂

    Thanks!

  • Love this script. Hope you don't mind, I added one tweak, to pass a time parameter in (default to 3 seconds). Changes bolded below.

    if exists (select * from master.dbo.sysobjects where id = object_id('dbo.sp_whocpu') )

    Drop Procedure dbo.sp_whocpu

    go

    /*====================================================================

    -- Mircea Anton Nita - 2010

    -- https://www.mcpvirtualbusinesscard.com/VBCServer/Mircea/card

    ======================================================================*/

    Create Procedure dbo.sp_whocpu

    @samplingTime int = 3, -- seconds to pass, but maybe don't get carried away

    @dbname sysname = null,

    @loginame sysname = null

    as

    set nocount on

    declare

    @retcode int

    ,@sidlow varbinary(85)

    ,@sidhigh varbinary(85)

    ,@sid1 varbinary(85)

    ,@spidlow int

    ,@spidhigh int

    ,@seldbid varchar(10)

    ,@charMaxLenLoginName varchar(24)

    ,@charMaxLenDBName varchar(24)

    ,@charMaxLenCPUTime varchar(10)

    ,@charMaxLenCPUDelta varchar(10)

    ,@charMaxLenDiskIO varchar(10)

    ,@charMaxLenHostName varchar(24)

    ,@charMaxLenProgramName varchar(10)

    ,@charMaxLenLastBatch varchar(10)

    ,@charMaxLenCommand varchar(10)

    ,@charsidlow varchar(85)

    ,@charsidhigh varchar(85)

    ,@charspidlow varchar(11)

    ,@charspidhigh varchar(11)

    ,@command varchar(8000)

    ,@samplingTimeString varchar(10) -- string version of sampleTime to pass to WAITFOR DELAY

    -- CHANGES TO TAKE VARIABLE SAMPLING TIME

    if @samplingTime < 3 set @samplingTime = 3 -- use the acceptable minimum

    SELECT @samplingTimeString = cast(

    (

    CASE WHEN @samplingTime/3600<10 THEN '0' ELSE '' END

    + RTRIM(@samplingTime/3600)

    + ':' + RIGHT('0'+RTRIM((@samplingTime % 3600) / 60),2)

    + ':' + RIGHT('0'+RTRIM((@samplingTime % 3600) % 60),2)

    ) as varchar(10))

    -- set defaults

    set @retcode = 0

    set @sidlow = convert(varbinary(85), (replicate(char(0), 85)))

    set @sidhigh = convert(varbinary(85), (replicate(char(1), 85)))

    set @spidlow = 0

    set @spidhigh = 32767

    if (@dbname is not null)

    set @seldbid = cast((select top 1 dbid from master.dbo.sysdatabases where name like '%'+@dbname+'%') as varchar(10))

    else

    set @seldbid = '0'

    if (@loginame is null) -- Simple default to all LoginNames.

    GOTO LABEL_PARAM

    select @sid1 = null

    if exists(select * from sys.syslogins where loginname = @loginame)

    select @sid1 = sid from sys.syslogins where loginname = @loginame

    if (@sid1 is not null) -- The parameter is a recognized login name.

    begin

    select @sidlow = suser_sid(@loginame)

    ,@sidhigh = suser_sid(@loginame)

    GOTO LABEL_PARAM

    end

    if (lower(@loginame collate Latin1_General_CI_AS) in ('Active')) -- Special action, not sleeping.

    begin

    select @loginame = lower(@loginame collate Latin1_General_CI_AS)

    GOTO LABEL_PARAM

    end

    if (patindex ('%[^0-9]%' , isnull(@loginame,'z')) = 0) -- Is a number.

    begin

    select

    @spidlow = convert(int, @loginame)

    ,@spidhigh = convert(int, @loginame)

    GOTO LABEL_PARAM

    end

    raiserror(15007,-1,-1,@loginame)

    select @retcode = 1

    GOTO LABEL_RETURN

    LABEL_PARAM:

    -- Getting data over a time window to allow the cpu_delta metric calculation

    if object_id('tempdb.dbo.#cpu1') is not null drop table #cpu1

    if object_id('tempdb.dbo.#cpu2') is not null drop table #cpu2

    select spid, cpu into #cpu1 from master.dbo.sysprocesses with (nolock) order by cpu desc

    waitfor delay @sampling_time_string

    select spid, cpu into #cpu2 from master.dbo.sysprocesses with (nolock) order by cpu desc

    -------------------- Capture consistent sysprocesses. -------------------

    select

    sp.spid

    ,status

    ,sid

    ,hostname

    ,program_name

    ,cmd

    ,sp.cpu

    ,c2.cpu-c1.cpu as 'cpu_delta'

    ,physical_io

    ,blocked

    ,dbid

    ,convert(sysname, rtrim(loginame)) as loginname

    ,sp.spid as 'spid_sort'

    , substring( convert(varchar,last_batch,111) ,6 ,5 ) + ' '

    + substring( convert(varchar,last_batch,113) ,13 ,8 ) as 'last_batch_char'

    into #tb1_sysprocesses

    from #cpu2 c2 join #cpu1 c1 on c2.spid = c1.spid join master.dbo.sysprocesses sp with (nolock) on sp.spid = c2.spid

    where c2.cpu-c1.cpu > 0

    if @@error <> 0

    begin

    select @retcode = @@error

    GOTO LABEL_RETURN

    end

    if (@loginame in ('active'))

    delete #tb1_sysprocesses

    where lower(status) = 'sleeping'

    and upper(cmd) in (

    'AWAITING COMMAND'

    ,'LAZY WRITER'

    ,'CHECKPOINT SLEEP'

    )

    and blocked = 0

    and dbid <> @seldbid

    -- Prepare to dynamically optimize column widths.

    select

    @charsidlow = convert(varchar(85),@sidlow)

    ,@charsidhigh = convert(varchar(85),@sidhigh)

    ,@charspidlow = convert(varchar,@spidlow)

    ,@charspidhigh = convert(varchar,@spidhigh)

    select

    @charMaxLenLoginName =

    convert( varchar

    ,isnull( max( datalength(loginname)) ,16)

    )

    ,@charMaxLenDBName =

    convert( varchar

    ,isnull( max( datalength( rtrim(convert(varchar(128),db_name(dbid))))) ,20)

    )

    ,@charMaxLenCPUTime =

    convert( varchar

    ,isnull( max( datalength( rtrim(convert(varchar(128),cpu)))) ,10)

    )

    ,@charMaxLenCPUDelta =

    convert( varchar

    ,isnull( max( datalength( rtrim(convert(varchar(128),cpu_delta)))) ,10)

    )

    ,@charMaxLenDiskIO =

    convert( varchar

    ,isnull( max( datalength( rtrim(convert(varchar(128),physical_io)))) ,6)

    )

    ,@charMaxLenCommand =

    convert( varchar

    ,isnull( max( datalength( rtrim(convert(varchar(128),cmd)))) ,7)

    )

    ,@charMaxLenHostName =

    convert( varchar

    ,isnull( max( datalength( rtrim(convert(varchar(128),hostname)))) ,16)

    )

    ,@charMaxLenProgramName =

    convert( varchar

    ,isnull( max( datalength( rtrim(convert(varchar(128),program_name)))) ,11)

    )

    ,@charMaxLenLastBatch =

    convert( varchar

    ,isnull( max( datalength( rtrim(convert(varchar(128),last_batch_char)))) ,9)

    )

    from

    #tb1_sysprocesses

    where

    spid >= @spidlow

    and spid <= @spidhigh

    -- Output the report.

    set @command = '

    set nocount off

    select

    SPID = convert(char(5),spid)

    ,Status =

    CASE lower(status)

    When ''sleeping'' Then lower(status)

    Else upper(status)

    END

    ,Login = substring(loginname,1,' + @charMaxLenLoginName + ')

    ,HostName =

    CASE hostname

    When Null Then '' .''

    When '' '' Then '' .''

    Else substring(hostname,1,' + @charMaxLenHostName + ')

    END

    ,BlkBy =

    CASE isnull(convert(char(5),blocked),''0'')

    When ''0'' Then '' .''

    Else isnull(convert(char(5),blocked),''0'')

    END

    ,DBName = substring(case when dbid = 0 then null when dbid <> 0 then db_name(dbid) end,1,' + @charMaxLenDBName + ')

    ,Command = substring(cmd,1,' + @charMaxLenCommand + ')

    ,CPU_Total = substring(convert(varchar,cpu),1,' + @charMaxLenCPUTime + ')

    ,CPU_Delta = substring(convert(varchar,cpu_delta),1,' + @charMaxLenCPUDelta + ')

    ,DiskIO = substring(convert(varchar,physical_io),1,' + @charMaxLenDiskIO + ')

    ,LastBatch = substring(last_batch_char,1,' + @charMaxLenLastBatch + ')

    ,ProgramName = substring(program_name,1,' + @charMaxLenProgramName + ')

    ,SPID = convert(char(5),spid) -- Handy extra for right-scrolling users.

    from

    #tb1_sysprocesses

    where spid > 50 -- filter out system spids

    and spid <> @@spid -- and current process spid

    and spid >= ' + @charspidlow + '

    and spid <= ' + @charspidhigh + '

    '

    if @seldbid > 0

    set @command = @command +

    '

    and dbid = ' + @seldbid + '

    '

    set @command = @command +

    ' order by cast(cpu_delta as int) desc, cast(cpu as int) desc

    set nocount on

    '

    exec (@command)

    LABEL_RETURN:

    if object_id('tempdb.dbo.#tb1_sysprocesses') is not null drop table #tb1_sysprocesses

    if object_id('tempdb.dbo.#cpu1') is not null drop table #cpu1

    if object_id('tempdb.dbo.#cpu2') is not null drop table #cpu2

    return @retcode -- sp_whocpu

    go

    if exists (select * from sysobjects

    where id = object_id('dbo.sp_whocpu')

    and sysstat & 0xf = 4)

    grant exec on dbo.sp_whocpu to public

    go

    Gaby________________________________________________________________"In theory, theory and practice are the same. In practice, they are not." - Albert Einstein

  • Hi,

    Thank you very much for your comments and your suggestion.

    The stored procedure did have an interval parameter in the design phase, however, I found in the past two years since using it that 2 seconds is the minimum time to get meaningful figures, and from 4 or 5 seconds onwards the wait until you get results is too long.

    You can certainly use a parameter for the interval, however, this opens new possibilities for things to go astray, as many DBAs including me think of time in milliseconds, and it would be easy to pass by mistake 4000 instead of 4 as parameter if you have four seconds in mind. This would be less than ideal.

    The main use for this stored procedure is as a very fast tool to get the top processes consuming cpu, so although I am generally against hard coding, I decided not to use parameters - just call sp_whocpu and get the results.

    Thanks,

    Mircea

  • Hello,

    You are deleting sleeping processes if the @loginame is in 'Active'. But what happens if I don't give any login name, which means @loginame would be null? Does the procedure still delete the sleeping processes from the temporary table?

    Thanks.

  • The query has no sense at all! I urge everyone not to use it.

    This join based on spid is simply wrong

    from #cpu2 c2 join #cpu1 c1 on c2.spid = c1.spid join master.dbo.sysprocesses sp with (nolock) on sp.spid = c2.spid


    Alex Suprun

  • Hi Alex,

    Thank you for looking into this script.

    Can you please substantiate your claim and explain why it doesn't make sense?

    We are always willing to improve the quality of our scrips.

    It was not the purpose of the post to explain how this works, since the full source code was published for you to analyse.

    There are comments within the script which explain the idea of two sysprocesses snapshots at 3 seconds interval, comments which we thought are sufficient for all T-SQL users.

    I did not urge anyone to use the script, so please short of explaining exactly why - do not urge anyone to do anything else but analyse the script and decide for themselves whether to use it or not.

  • Mircea (5/21/2015)


    I did not urge anyone to use the script, so please short of explaining exactly why - do not urge anyone to do anything else but analyse the script and decide for themselves whether to use it or not.

    I thought that the whole purpose of posting ready-to-use scripts is that other people don't have to spend a lot of time doing code review and making sure that script does what is was designed to do.

    To name a few:

    1. spid is not unique in sysprocesses

    2. spid can be easily assigned to another connection from different user during 3 seconds interval

    3. cpu in sysprocesses will show only cpu consumed by main thread in multi-threaded plan


    Alex Suprun

  • Thanks for the script.

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