Hey, I'm playing with a Linux embedded box. Some time ago, we (finally) switched from kernel 2.4.36 to 2.6.18.8. Naturally libc was also upgraded. What have not changed was the sources of the applications: Firefox 2.0 running on top of custom X server. GTK/pango/cairo/etc are also identical in both systems. So far so good, yet we have found out that the kernel/libc upgrade basically broke the customer's code: CSS/Javascript timers driven application, running inside the browser, which started to run much slower, from user experience point of view. Unfortunately, the customer's user experience is extremely important ;)
Black box analysis showed differences in system behavior, see bellow. Any idea about what else should be checked are greatly appreciated. And yeah, the final goal is a happy customer. Please share you thoughts - bounce some ideas. Thanks in advance, ~baum --------------------------------------------------------------------------------------------------------------------------------------------------------------------- TOP 2.4 The system CPU is 5% idle, utilization is between browser and X server in 60%-40% ratio. 2.6 The system CPU is 80% idle, utilization is between browser and X server in 60%-40% ratio. --------------------------------------------------------------------------------------------------------------------------------------------------------------------- STRACE (strace -c -p PID / during 100 secs). NOTE: In case of Firefox, it is not a really apple to apple comparison, since only "active thread" pid was straced. 2.4 kernel - "FAST user experience" X server % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 90.70 15.259293 1045 14600 204 select 4.55 0.765248 19 39678 11956 read 3.59 0.604554 33 18350 2 writev 0.52 0.087052 62 1415 munmap 0.46 0.077625 3 29071 gettimeofday 0.10 0.017304 3 4951 1821 sigreturn 0.07 0.011463 8 1415 old_mmap 0.01 0.002002 3 764 setitimer ------ ----------- ----------- --------- --------- ---------------- 100.00 16.824541 110244 13983 total Firefox browser ------ ----------- ----------- --------- --------- ---------------- 47.54 3.022460 1947 1552 select 19.00 1.207781 272 4446 poll 12.43 0.789926 41 19280 write 8.32 0.529035 29 18218 37 readv 7.37 0.468285 179 2618 2 writev 1.51 0.095897 5 19428 1253 read 1.20 0.076559 50 1544 old_mmap 0.75 0.047951 7 6426 brk 0.64 0.040452 9 4471 ioctl 0.58 0.036982 24 1545 munmap 0.57 0.035924 2 15927 gettimeofday 0.09 0.005809 5 1156 kill ------ ----------- ----------- --------- --------- ---------------- 100.00 6.357061 96611 1292 total 2.6 kernel - "SLOW user experience" X server % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 55.00 0.003374 1 5287 writev 35.18 0.002158 0 8580 2217 select 9.81 0.000602 0 14486 6008 read 0.00 0.000000 0 17114 gettimeofday 0.00 0.000000 0 41 munmap 0.00 0.000000 0 4454 setitimer 0.00 0.000000 0 2543 2479 sigreturn 0.00 0.000000 0 41 mmap2 ------ ----------- ----------- --------- --------- ---------------- 100.00 0.006134 52546 10704 total Firefox browser % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 81.95 0.021973 3 7421 writev 13.55 0.003634 0 13674 5906 read 3.68 0.000986 0 13012 select 0.51 0.000138 1 170 stat64 0.31 0.000082 1 118 futex 0.00 0.000000 0 90 write 0.00 0.000000 0 1789 gettimeofday 0.00 0.000000 0 249 poll ------ ----------- ----------- --------- --------- ---------------- 100.00 0.026813 36523 5906 total _______________________________________________ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
