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Diffstat (limited to 'poky/documentation/profile-manual/usage.rst')
| -rw-r--r-- | poky/documentation/profile-manual/usage.rst | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/poky/documentation/profile-manual/usage.rst b/poky/documentation/profile-manual/usage.rst index ae4efa7f4c..3d2840884f 100644 --- a/poky/documentation/profile-manual/usage.rst +++ b/poky/documentation/profile-manual/usage.rst @@ -105,18 +105,18 @@ can be used in a very similar way to the whole host of supported BusyBox applets in Yocto. :: root@crownbay:~# rm linux-2.6.19.2.tar.bz2; \ - wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2 + wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2 The quickest and easiest way to get some basic overall data about what's going on for a particular workload is to profile it using 'perf stat'. 'perf stat' basically profiles using a few default counters and displays the summed counts at the end of the run:: - root@crownbay:~# perf stat wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2 + root@crownbay:~# perf stat wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2 Connecting to downloads.yoctoproject.org (140.211.169.59:80) linux-2.6.19.2.tar.b 100% |***************************************************| 41727k 0:00:00 ETA - Performance counter stats for 'wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2': + Performance counter stats for 'wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2': 4597.223902 task-clock # 0.077 CPUs utilized 23568 context-switches # 0.005 M/sec @@ -141,11 +141,11 @@ by 'perf stat'. For example, suppose we wanted to see a summary of all the events related to kernel memory allocation/freeing along with cache hits and misses:: - root@crownbay:~# perf stat -e kmem:* -e cache-references -e cache-misses wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2 + root@crownbay:~# perf stat -e kmem:* -e cache-references -e cache-misses wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2 Connecting to downloads.yoctoproject.org (140.211.169.59:80) linux-2.6.19.2.tar.b 100% |***************************************************| 41727k 0:00:00 ETA - Performance counter stats for 'wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2': + Performance counter stats for 'wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2': 5566 kmem:kmalloc 125517 kmem:kmem_cache_alloc @@ -181,7 +181,7 @@ executed in a new shell). perf collects samples until the process exits and records them in a file named 'perf.data' in the current working directory. :: - root@crownbay:~# perf record wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2 + root@crownbay:~# perf record wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2 Connecting to downloads.yoctoproject.org (140.211.169.59:80) linux-2.6.19.2.tar.b 100% |************************************************| 41727k 0:00:00 ETA @@ -219,7 +219,7 @@ between the new profile and the previous one is that we'll add the -g option, which will record not just the address of a sampled function, but the entire callchain to the sampled function as well:: - root@crownbay:~# perf record -g wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2 + root@crownbay:~# perf record -g wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2 Connecting to downloads.yoctoproject.org (140.211.169.59:80) linux-2.6.19.2.tar.b 100% |************************************************| 41727k 0:00:00 ETA [ perf record: Woken up 3 times to write data ] @@ -527,8 +527,8 @@ workload, so let's choose the most likely subsystems (identified by the string before the colon in the Tracepoint events) and do a 'perf stat' run using only those wildcarded subsystems:: - root@crownbay:~# perf stat -e skb:* -e net:* -e napi:* -e sched:* -e workqueue:* -e irq:* -e syscalls:* wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2 - Performance counter stats for 'wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2': + root@crownbay:~# perf stat -e skb:* -e net:* -e napi:* -e sched:* -e workqueue:* -e irq:* -e syscalls:* wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2 + Performance counter stats for 'wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2': 23323 skb:kfree_skb 0 skb:consume_skb @@ -589,7 +589,7 @@ run using only those wildcarded subsystems:: Let's pick one of these tracepoints and tell perf to do a profile using it as the sampling event:: - root@crownbay:~# perf record -g -e sched:sched_wakeup wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2 + root@crownbay:~# perf record -g -e sched:sched_wakeup wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2 .. image:: figures/sched-wakeup-profile.png :align: center @@ -648,7 +648,7 @@ applicable to our workload:: root@crownbay:~# perf record -g -e skb:* -e net:* -e napi:* -e sched:sched_switch -e sched:sched_wakeup -e irq:* -e syscalls:sys_enter_read -e syscalls:sys_exit_read -e syscalls:sys_enter_write -e syscalls:sys_exit_write - wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2 + wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2 We can look at the raw trace output using 'perf script' with no arguments:: @@ -885,7 +885,7 @@ To demonstrate this, open up one window and start the profile using the In another window, run the wget test:: - root@crownbay:~# wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2 + root@crownbay:~# wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2 Connecting to downloads.yoctoproject.org (140.211.169.59:80) linux-2.6.19.2.tar.b 100% \|*******************************\| 41727k 0:00:00 ETA @@ -2251,7 +2251,7 @@ of the block device you want to trace activity on:: In another shell, execute a workload you want to trace. :: - root@crownbay:/media/sdc# rm linux-2.6.19.2.tar.bz2; wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2; sync + root@crownbay:/media/sdc# rm linux-2.6.19.2.tar.bz2; wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2; sync Connecting to downloads.yoctoproject.org (140.211.169.59:80) linux-2.6.19.2.tar.b 100% \|*******************************\| 41727k 0:00:00 ETA @@ -2420,7 +2420,7 @@ On the target system, you should see this:: In another shell, execute a workload you want to trace. :: - root@crownbay:/media/sdc# rm linux-2.6.19.2.tar.bz2; wget http://downloads.yoctoproject.org/mirror/sources/linux-2.6.19.2.tar.bz2; sync + root@crownbay:/media/sdc# rm linux-2.6.19.2.tar.bz2; wget &YOCTO_DL_URL;/mirror/sources/linux-2.6.19.2.tar.bz2; sync Connecting to downloads.yoctoproject.org (140.211.169.59:80) linux-2.6.19.2.tar.b 100% \|*******************************\| 41727k 0:00:00 ETA |