SBR600: To Thumb? or Not to Thumb? (v0.2)

Hi all, this is  version 0.2 of my project, To Thumb? or Not to Thumb?

I'm going to start off with some additional benchmark results.

abiword-2.8.1

Produced RPM: libabiword-2.8.1-1.fc12.armv5tel.rpm

Directories and files: 39 directories, 617 files

Binary File: usr/lib/libabiword-2.8

	w/o Thumb	THUMB	THUMB2	THUMB / NON-THUMB	THUMB / THUMB2
RPM	5561088	4779800	4742828	0.8595	1.0078
Directory	21295155	17055836	16987340	0.8009	1.0040
Binary	5806908	3450936	3371440	0.5943	1.0236

tar-1.22

Produced RPM: tar-1.22-8.fc12.armv5tel.rpm

Directories and files: 79 directories, 49 files

Binary File: bin/tar

	w/o Thumb	THUMB	THUMB2	THUMB / NON-THUMB	THUMB / THUMB2
RPM	744340	742784	742180	0.9979	1.0008
Directory	2737195	2681159	2675975	0.9795	1.0019
Binary	251844	195808	190624	0.7775	1.0272

So based on my benchmarks so far, THUMB reduced the sizes about

3% for *.rpm files,

9% for extracted directories, and

24% for executables, in average.

While it might save some disk space for executable files, it doesn't make a big different for rpm packages since rpm has it's own compressing mechanism.

In terms of performance of binaries that are built with THUMB and non-THUMB, there weren't too many programs that I could efficiently test in the command line interface. For now, I've ran some tests with tar binaries that I compiled.

I've downloaded source code for openoffice (openoffice.org-3.1.1-19.34.fc12.src.rpm), extracted twice to two separate directories, and compiled each one of them with tar binary that was compiled with THUMB, and without THUMB. I've done every test 4 times for better accuracy.

System: cdot-guru-4-1

File: Extracted openoffice.org-3.1.1-19.34.fc12.src.rpm

Command Used: time ./tar -cvf nothumb.tar ~/temp

	w/o Thumb	THUMB
1st Attempt	real 0m33.013s user 0m0.090s sys 0m3.800s	real 0m45.746s user 0m0.170s sys 0m3.710s
2nd Attempt	real 0m38.410s user 0m0.150s sys 0m3.860s	real 0m40.039s user 0m0.130s sys 0m3.760s
3rd Attempt	real 0m37.572s user 0m0.110s sys 0m3.820s	real 0m42.034s user 0m0.140s sys 0m3.820s
4th Attempt	real 0m36.934s user 0m0.150s sys 0m3.670s	real 0m43.051s user 0m0.100s sys 0m3.830s

The tar that was compiled with THUMB was compressing little bit slower in every attempts. Just to confirm that both tars compressed correctly, I've checked sizes of tarballs.

-rw-rw-r-- 1 thlee3 thlee3 218183680 2010-11-26 10:43 nothumb.tar

-rw-rw-r-- 1 thlee3 thlee3 218183680 2010-11-26 10:41 thumb.tar

And they seemed ok.

As a second test, I've tried decompressing one of the tarballs I created in the first test, using both tars.

System: cdot-guru-4-1

File: nothumb.tar

Command Used: time ~/tar.mthumb-interwork/bin/tar -xvf nothumb.tar

	w/o Thumb	THUMB
1st Attempt	real 0m48.399s user 0m0.170s sys 0m3.560s	real 0m54.197s user 0m0.160s sys 0m3.480s
2nd Attempt	real 0m46.306s user 0m0.170s sys 0m3.280s	real 0m48.234s user 0m0.160s sys 0m3.680s
3rd Attempt	real 0m45.602s user 0m0.130s sys 0m3.800s	real 0m49.501s user 0m0.150s sys 0m3.490s
4th Attempt	real 0m46.546s user 0m0.110s sys 0m3.420s	real 0m52.897s user 0m0.120s sys 0m3.460s

Again, the tar that was built with THUMB decompressed the tarball little bit slower. I should focus more into performance difference between binaries that are built with THUMB and non-THUMB in this project.

I've also made records of the duration rpmbuild took for compiling. I'd like to say that I did not notice any major difference in compiling times, although it'd be hard measure this accurately because compiling durations fluctuated in every attempts I made.

	w/o Thumb	THUMB
nled	real 0m13.701s user 0m12.190s sys 0m1.020s	real 0m14.821s user 0m11.830s sys 0m1.060s
wget	real 3m57.207s user 3m1.920s sys 0m40.610s	real 3m59.251s user 3m0.750s sys 0m39.810s
gimp	real 112m40.989s user 92m48.050s sys 10m34.130s	real 110m46.166s user 90m13.740s sys 10m32.150s
abiword	real 148m58.630s user 130m32.050s sys 8m51.320s	real 140m30.739s user 123m38.600s sys 8m46.910s

Some of the difficulties I had while I was working this project are one or more dependencies required for compiling are not available for armv5tel architecture. For example, I was not able to compile openoffice.org because lucene was needed but not yet available. Another challenge was my lack of knowledge in c language and gcc. Once rpmbuild encounters an error in the middle of compiling, it would stop and I wasn't able to make correction in the spec file. I'd like to try compiling mysql and postgresql once I figure this out.

So this concludes my version 0.2. Thank you very much and please stay tuned for version 0.3.