Besides,the trace statement shows 
create function tracelog() 
	returns table (
		event integer,		-- event counter
		clk varchar(20), 	-- wallclock, no mtime in kernel
		pc varchar(50), 	-- module.function[nr]

		thread int, 		-- thread identifier
		ticks integer, 		-- time in microseconds
		reads integer, 		-- number of blocks read
		writes integer, 	-- number of blocks written
		rbytes integer,		-- amount of bytes touched

		wbytes integer,		-- amount of bytes written
		type string,		-- return types
		stmt string			-- actual statement executed
	)
	external name sql.dump_trace;

What's the meaning of clk and ticks? How to use them for performance test?

Really sorry that I could not understand the comments.

Thanks,
Mo



On Mon, Feb 8, 2010 at 3:59 PM, Mo Zhou <mozhou@umail.iu.edu> wrote:
Hi,

Sorry for bothering you again...
I am confused by the time shown in Timer/queryHistory/callHistory.
In queryHistory, there are two time: parse time and optimization time.
In callHistory, there are two important time: xtime and rtime.
These times should not overlap each other.

but when I sum up these times, the number is different from the one returned by Timer.
I wonder which time should I use for performance test.

Thank you very much.

--
Thanks,
Mo



--
Thanks,
Mo