| Summary: | Incorrect values for parameters using process().function() | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Dave Malcolm <dmalcolm> |
| Component: | systemtap | Assignee: | Frank Ch. Eigler <fche> |
| Status: | CLOSED CURRENTRELEASE | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | medium | Docs Contact: | |
| Priority: | low | ||
| Version: | 12 | CC: | fche, jistone, mjw, mjw, roland, wcohen |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2010-02-21 18:02:42 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | ||
| Bug Depends On: | |||
| Bug Blocks: | 546295 | ||
This could be related to systemtap PR 10601, which we're expecting to fix for an impending next release of systemtap. > This could be related to systemtap PR 10601, which we're expecting to fix for > an impending next release of systemtap. URL: http://sourceware.org/bugzilla/show_bug.cgi?id=10601 I notice that you marked http://sourceware.org/bugzilla/show_bug.cgi?id=10601 as RESOLVED FIXED on 2009-12-21 - thanks. Are these fixes in rawhide yet? (pretty-please!) (In reply to comment #3) > I notice that you marked http://sourceware.org/bugzilla/show_bug.cgi?id=10601 > as RESOLVED FIXED on 2009-12-21 - thanks. > > Are these fixes in rawhide yet? (pretty-please!) Yes, they should be available with systemtap-1.1-1.fc13. This also provides the systemtap dtrace -I script support. (In reply to comment #0) > I'm also sometimes seeing error messages in pass 1 of the > form: > semantic error: No cfa_ops supplied, but needed by DW_OP_call_frame_cfa > when I make the script more complex; should I file that as a separate bug? Yes please, if you see it after updating to systemtap-1.1. There has been one bug fix for 1.1 that addresses one case of DW_OP_call_frame_cfa not being found, but there seems to be some other issue lurking out there. If you get anything with a good reproducer that would be very appreciated. > > I'm also sometimes seeing error messages in pass 1 of the > > form: > > semantic error: No cfa_ops supplied, but needed by DW_OP_call_frame_cfa > > when I make the script more complex; should I file that as a separate bug? > Yes please, if you see it after updating to systemtap-1.1. Still seeing this with 1.1; filed as bug 556944 With systemtap-1.1-2.fc12.i686 I am seeing:
$ stap -e 'probe process("/usr/lib/libpython2.6.so.1.0").function("PyObject_Malloc") { printf("PyObject_Malloc(%i)\n", $nbytes); }' -c "python -c 'import gtk; import dbus'"
PyObject_Malloc(24)
PyObject_Malloc(35)
PyObject_Malloc(136)
PyObject_Malloc(31)
PyObject_Malloc(136)
PyObject_Malloc(31)
PyObject_Malloc(31)
PyObject_Malloc(32)
PyObject_Malloc(35)
PyObject_Malloc(36)
[... lots of different numbers ...]
Do these numbers make sense now?
Thanks! This is now working well
systemtap-1.1-2.fc12.i686
systemtap-sdt-devel-1.1-1.fc12.i686
systemtap-runtime-1.1-2.fc12.i686
The numbers below appear credible; here's an example of the 3 levels of memory allocations, running: python -c"pass"; hope to use this to improve Python's heap-usage behavior.
PyObject_Malloc calls:
value |-------------------------------------------------- count
0 | 0
1 | 35
2 |@ 322
4 |@ 233
8 | 90
16 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 8855
32 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 10481
64 |@@@@@@@@ 1850
128 |@@ 588
256 |@@ 428
512 |@@ 538
1024 | 16
2048 | 6
4096 | 1
8192 | 1
16384 | 0
32768 | 0
PyMem_Malloc calls:
value |-------------------------------------------------- count
1 | 0
2 | 0
4 |@@@@@@@@@@@ 11
8 | 0
16 |@@@@@@@@@@@@@@@@@@@@@@ 22
32 |@@@@@@@@@@@@@@@ 15
64 | 0
128 |@@@@@ 5
256 | 0
512 |@@@@@@@@ 8
1024 | 0
2048 | 0
4096 | 0
8192 |@@@@@@@@@@@@@@@@ 16
16384 | 0
32768 | 0
malloc calls:
value |-------------------------------------------------- count
0 | 0
1 | 1
2 | 1
4 |@@@@@@@@@ 179
8 |@@@@@@@@@@@@@@@ 300
16 |@@@@@@@@@@@@@@@@@@@@@@@ 451
32 |@@@@@@ 127
64 |@ 19
128 |@ 23
256 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 905
512 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 576
1024 |@@@@@@@@@@ 205
2048 | 8
4096 | 16
8192 |@ 32
16384 |@ 20
32768 | 4
65536 | 1
131072 | 0
262144 | 3
524288 | 0
1048576 | 0
|
Description of problem: I'm attempting to use systemtap to probe Python's usage of the heap, but ran into an issue with getting the args to the various user-space functions. Here's a (very) simplified version of the script I'm trying (python-mem.stp): probe process("/usr/lib/libpython2.6.so.1.0").function("PyObject_Malloc") { printf("PyObject_Malloc(%i)\n", $nbytes); } with the hope of probing this function inside libpython2.6.so.1.0: void * PyObject_Malloc(size_t nbytes) { (snip large, complicated implementation, using arenas on top of malloc) } I try running it thus: stap -v python-mem.stp -c "python -c 'import gtk; import dbus'" The output is a series of lines: stap -v python-mem.stp -c "python -c 'import gtk; import dbus'" Pass 1: parsed user script and 59 library script(s) in 210usr/20sys/233real ms. Pass 2: analyzed script: 1 probe(s), 1 function(s), 0 embed(s), 0 global(s) in 30usr/0sys/45real ms. Pass 3: translated to C into "/tmp/stapw9tHdC/stap_7df6edc8c0d40522be12c31a11cb120d_1331.c" in 110usr/0sys/125real ms. Pass 4, preamble: verifying that SystemTap's version of uprobes is up to date. Pass 4: compiled C into "stap_7df6edc8c0d40522be12c31a11cb120d_1331.ko" in 2530usr/490sys/3208real ms. Pass 5: starting run. PyObject_Malloc(123) PyObject_Malloc(123) PyObject_Malloc(123) PyObject_Malloc(123) PyObject_Malloc(123) PyObject_Malloc(123) (etc, all lines have value 123) Version-Release number of selected component (if applicable): $ rpm -qa systemtap\* kernel\* python python-libs python-debuginfo | sort kernel-debuginfo-common-i686-2.6.31.6-145.fc12.i686 kernel-firmware-2.6.31.6-145.fc12.noarch kernel-headers-2.6.31.6-145.fc12.i686 kernel-PAE-2.6.30.9-90.fc11.i686 kernel-PAE-2.6.30.9-96.fc11.i686 kernel-PAE-2.6.31.6-145.fc12.i686 kernel-PAE-debuginfo-2.6.31.6-145.fc12.i686 kernel-PAE-devel-2.6.30.9-90.fc11.i686 kernel-PAE-devel-2.6.30.9-96.fc11.i686 kernel-PAE-devel-2.6.31.6-145.fc12.i686 python-2.6.2-2.fc12.i686 python-debuginfo-2.6.2-2.fc12.i686 python-libs-2.6.2-2.fc12.i686 systemtap-1.0-2.fc12.i686 systemtap-runtime-1.0-2.fc12.i686 systemtap-sdt-devel-1.0-2.fc12.i686 How reproducible: 100% on this box; I'm also sometimes seeing error messages in pass 1 of the form: semantic error: No cfa_ops supplied, but needed by DW_OP_call_frame_cfa when I make the script more complex; should I file that as a separate bug? Steps to Reproduce: 1. as above Actual results: All lines are output with "123" as the value Expected results: Varying values, reflecting the sizes of the allocations, allowing me to get useful insight into how Python is using the heap.