Concerning the benchmark, I suggest to use $ROOTSYS/test/stress.cxx
in addition to the conventional interactive tutorials/benchmarks.C
The stress.cxx program is a collection of 16 test programs using
the main features of the ROOT system. It puts more emphasys on I/O.
To run this program go to the directory $ROOTSYS/test
make on linux
gmake on other Unix systems
nmake on NT
then
stress this will take several minutes to complete. At the end you get
a table like below with a ROOTMARK number.
For more info about stress, see comments at the top of stress.cxx
You can also run stress.cxx under CINT. This is a good measurement
of the performance of CINT compared to the native compiler.
root
Root > .x stress.cxx(1000)
Example of output on a Pentium II 400 Mhz with Linux/egcs1.1
******************************************************************
* Starting R O O T - S T R E S S test suite with 1000 events
******************************************************************
Test 1 : Functions, Random Numbers, Histogram Fits............. OK
Test 2 : Check size & compression factor of a Root file........ OK
Test 3 : Purge, Reuse of gaps in TFile......................... OK
Test 4 : Test of 2-d histograms, functions, 2-d fits........... OK
Test 5 : Test graphics & Postscript............................ OK
Test 6 : Test subdirectories in a Root file.................... OK
Test 7 : TNtuple, selections, TCut, TCutG, TEventList.......... OK
Test 8 : Trees split and compression modes..................... OK
Test 9 : Analyze Event.root file of stress 8................... OK
Test 10 : Create 10 files starting from Event.root.............. OK
Test 11 : Test chains of Trees using the 10 files............... OK
Test 12 : Compare histograms of test 9 and 11................... OK
Test 13 : Test merging files of a chain......................... OK
Test 14 : Check correct rebuilt of Event.root in test 13........ OK
Test 15 : Divert Tree branches to separate files................ OK
Test 16 : CINT test (3 nested loops) with LHCb trigger.......... OK
******************************************************************
* Linux pcbrun.cern.ch 2.2.3 #1 SMP Wed Mar 10 18:34:46 MET 1
******************************************************************
stress : Total I/O = 425.6 Mbytes, I = 296.4, O = 129.3
stress : Compr I/O = 407.4 Mbytes, I = 286.3, O = 121.0
stress : Real Time = 112.73 seconds Cpu Time = 102.66 seconds
******************************************************************
* ROOTMARKS = 136.0 * Root 2.21/07 990311/844
******************************************************************
Rene Brun