Hi,
I was trying to build Linux Benchmarks with latest Intel C++ Compiler.
When I used -ipo (inter-procedural optimization) option, arithmetic test (arith.c) failed on execution.

The problem is Intel compiler's advanced optimization option (-ipo) optimizes much more than expected and this results in elimination of some part of code.
/-------------------------------------------------
++iter;
/* the loop calls a function to insure that something is done
the results of the function are fed back in (just so they
they won't be thrown away. A loop with
unused assignments may get optimized out of existence */
result = dumb_stuff(result);
/--------------------------------------------------------

This part gets eliminated becuase of IPO.

Steps to reproduce:
$icc -o ./pgms/arithoh -DTIME -O3 -xW -ipo -static -unroll -Darithoh ./src/arith.c

$./pgms/arithoh 1
0 loops

and this results in divide by zero error.

Regards,
CP

Why are you using the -ipo compiler flag?

Neo

Hi Neo,
I have seen, in this forum, that developers have used advanaced gcc optimization options for benchmarking.
I just want to compare the performance of gcc and Intel compiler and thats why trying to use best available optimization options for Intel compiler i.e -ipo (PGO can also be used).

If this doesnt answer your question than please let me know why one should not be allowed to use whatever options available with a compiler for these benchmarks?

Regards,
CP

This is a point that has been long debated.... i.e. should be benchmark be changed to reflect new compiler options or left as they are so they relate to all the benchmarks that were ran from the past.

I have always wanted to have the entire benchmark history/ tradition over time and have not been a fan of trying to optimize the marks with compiler flags that were not available in the past. The results of the marks will not be historically related to the beginning..... alpha-to-omega comparisons.


There have many many others who strongly dissagee and want to change them on the continuing basis. This 'tension' causes problems in the overall BM community, taking the fun out of it (and one of the reasons I stopped running the Linux BMs many years ago.)

Neo

CPU/Speed: AMD Duron 900Mhz
Ram: 512 PC133
Motherboard: EliteGroup K7S5A
266 / 200 FSB
SiS® 735 System Chipset
5 PCI slots, 1 4X AGP slot, 1 AMR slot
Disk: 40 Gig Maxtor EIDE
Load: 1 user, running pppd and httpd
Kernel: Linux 2.4.20-6
Kernel ELF?: yes
pgms: gcc 2.5.8 compiled;
options

==============================================================
 
  BYTE UNIX Benchmarks (Version 3.11)
  System -- Linux Tarball 2.4.20-6 #1 Thu Feb 27 10:01:19 EST 2003 i686 athlon i386 GNU/Linux
  Start Benchmark Run: Mon Dec 29 17:04:25 EST 2003
   2 interactive users.
Dhrystone 2 without register variables   1738794.9 lps   (10 secs, 6 samples)
Dhrystone 2 using register variables     1847801.6 lps   (10 secs, 6 samples)
Arithmetic Test (type = arithoh)         3742724.2 lps   (10 secs, 6 samples)
Arithmetic Test (type = register)        166336.4 lps   (10 secs, 6 samples)
Arithmetic Test (type = short)           157037.3 lps   (10 secs, 6 samples)
Arithmetic Test (type = int)             166494.3 lps   (10 secs, 6 samples)
Arithmetic Test (type = long)            166528.3 lps   (10 secs, 6 samples)
Arithmetic Test (type = float)           335329.0 lps   (10 secs, 6 samples)
Arithmetic Test (type = double)          335727.1 lps   (10 secs, 6 samples)
System Call Overhead Test                487088.3 lps   (10 secs, 6 samples)
Pipe Throughput Test                     541380.4 lps   (10 secs, 6 samples)
Pipe-based Context Switching Test        185194.6 lps   (10 secs, 6 samples)
Process Creation Test                      4576.9 lps   (10 secs, 6 samples)
Execl Throughput Test                      1059.3 lps   (9 secs, 6 samples)
File Read  (10 seconds)                  1642657.0 KBps  (10 secs, 6 samples)
File Write (10 seconds)                   95026.0 KBps  (10 secs, 6 samples)
File Copy  (10 seconds)                   37314.0 KBps  (10 secs, 6 samples)
File Read  (30 seconds)                  1202209.0 KBps  (30 secs, 6 samples)
File Write (30 seconds)                   75369.0 KBps  (30 secs, 6 samples)
File Copy  (30 seconds)                   24758.0 KBps  (30 secs, 6 samples)
C Compiler Test                             215.9 lpm   (60 secs, 3 samples)
Shell scripts (1 concurrent)                324.7 lpm   (60 secs, 3 samples)
Shell scripts (2 concurrent)                155.0 lpm   (60 secs, 3 samples)
Shell scripts (4 concurrent)                 81.7 lpm   (60 secs, 3 samples)
Shell scripts (8 concurrent)                 42.0 lpm   (60 secs, 3 samples)
Dc: sqrt(2) to 99 decimal places          31901.3 lpm   (60 secs, 6 samples)
Recursion Test--Tower of Hanoi            19793.6 lps   (10 secs, 6 samples)
 
 
                     INDEX VALUES
TEST                                        BASELINE     RESULT      INDEX
 
Arithmetic Test (type = double)               2541.7   335727.1      132.1
Dhrystone 2 without register variables       22366.3  1738794.9       77.7
Execl Throughput Test                           16.5     1059.3       64.2
File Copy  (30 seconds)                        179.0    24758.0      138.3
Pipe-based Context Switching Test             1318.5   185194.6      140.5
Shell scripts (8 concurrent)                     4.0       42.0       10.5
                                                                 =========
     SUM of  6 items                                                 563.3
     AVERAGE                                                          93.9

is there any way to write this file to a cd

What file? Sorry, which file are you talking about and who are you talking about writing it?

Neo