Profiling functions

Community Support
1

HI all.

I just curious about profiling a functions.

According guide at http://www.kdbfaq.com/kdb-faq/how-can-i-measure-the-performance-of-my-q-code.html 

I can profile scripts, but I want to profile functions and not sure that this approach is proper.

I can manually place \t inside my functions, aggregate results and show them, but this not smart.

I will be grateful for any advice.

2

Content-transfer-encoding: 8BIT

nick psaris’s forthcoming book on q contains some very nice profiling functions.

3

Hi Stevan, 

Sounds good! What will this book be focusing on? Will he be releasing soon? Should be a good read!

Hi Vadim,

I find the debug.q script, written by akozyrev, very useful. Located at - http://code.kx.com/wiki/Contrib/debugQ

There is a function in it that splits the function up to each line. Function is .d.rfn, and you should have a look. Using it we can expand on it, and as it is only time execution you are concerned about, then a simple timestamp will suffice. 

This (and memory usage per line) would be a good suggestion for the author, and at the bottom of the link above, he asks for suggestions too. Maybe it would be a good idea?

Anyway..here is a quickly written tool for what you require. *Very swiftly tested.

\l debug.q

F:{“{”,x,“}”}

P:{$[“[”=first foo:-1_1_last get x;:@[(foo?/:“”);1;+;1] sublist foo;:“”]}

T:{bar:@[.d.rfn x;where “:”=first each trim each .d.rfn x;1_];raze (“foo:.z.p;”,value bar,:“;foo:foo,.z.p;”),“foo”}

W:{[f;a](enlist each value[.d.rfn get f]),'1_deltas value[F P[get f],T get f] . a}

Wr:{[f;a]foo:W[f;a];`res insert (count[foo]#f;til count foo;foo[;0];foo[;1])}

res:(func:();line:();exe:();timeT:())

Lets define 2 random functions

f:{?[x;();0b;enlist[y]!enlist(sums;y)]}

f2:{[a;b;c;d]a*b;a+b;a*c;a*b*c*d;2000*a*d}

Lets run for each - pass function name and vars as if they were passed into it using “.”

Wr[`f2;(10;20;30;40)]

n:10000000

tab2:(c1:n?1000;c2:n?100.0;c3:n?100.0)

Wr[`f;(`tab2;`c1)]

Lets look at res tab now

q)res

func line exe                                       timeT

f2   0    “a * b;”                                  0D00:00:00.000000000

f2   1    “a+b;”                                    0D00:00:00.000000000

f2   2    “a * c;”                                  0D00:00:00.000000000

f2   3    “a * b * c * d;”                          0D00:00:00.000000000

f2   4    “: (2000)* a * d”                         0D00:00:00.000000000

f    0    “: ?[x;();0b;(enlist y)!enlist (sums;y)]” 0D00:00:00.046818000

HTH,

Sean

4

i’ve put mine here, only profiles time though

www.github.com/patmok/qprofiler

5

Thanks guys.
patmok’s version of profiling looks great.