Systemtap is tool to probe or trace a running linux system, supporting visibility into both kernel- (its initial focus) and user-space. It uses dynamically loaded probes to gather performance and tracing data about the whole system or just selected processes.
Questions tagged [systemtap]
142 questions
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Systemtap (stap) probes fail with "this statement may fall through [-Werror=implicit-fallthrough=]"
After a kernel update from 5.2 to 5.3.5 my SystemTAP (stap) probes are failing with errors like
/usr/share/systemtap/runtime/map-gen.c: In function ‘hash_si’:
/usr/share/systemtap/runtime/map-gen.c:114:28: error: this statement may fall through…
Craig Ringer
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1 answer
Solve systemtap (stap) "Spawn error (2): No such file or directory"
Running a previously working stap script I now get:
$ sudo PATH=$MORE_PATH_ENTRIES stap -v myscript.stp
...blahblah...
Pass 4: compilation failed. [man error::pass4]
with -vvv the output includes:
Running env -uARCH -uKBUILD_EXTMOD -uCROSS_COMPILE…
Craig Ringer
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1 answer
systemtap failed to probe the functions. Registration error
systemtap registration error.
WARNING: probe process("/home/user/a.out").function("func").return inode-offset 00000000468ed0c6 registration error (rc -5)
WARNING: probe process("/home/user/a.out").function("func").call inode-offset 00000000468ed0c6…
Franc
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Dumping a syscall argument of array type in systemtap
I am trying to dump a variable from a syscall probe in a systemtap script:
probe syscall.execve
{
printf("ARGS: %s\n", argstr)
print($envp)
print("\n")
}
After running a program under systemtap like this
sudo stap -vv -W script.stp -c…
Mikhail Maltsev
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1 answer
systemtap cannot work on Ubuntu: "unable to find a suitable compile server"
When I run systemtap on my Ubuntu, I always get this failure:
lwtools# ./biolatency-nd.stp
Using a compile server.
Unable to find a suitable compile server. [man stap-server]
No servers online to select from.
Passes: via server failed. Try again…
jackyard
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1 answer
what is python doing with systemtap?
I noticed on CentOS-7 distro that the python-2 and python-3 RPM installs both have some "systemtap" scripts installed at /usr/share/systemtap.
What is python doing with systemtap scripts?
I read a little about what is systemtap and the…
Trevor Boyd Smith
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1 answer
Handling long probe paths in systemtap userspace scripts (variables)?
I am trying to instrument a user-space program using systemtap, Linux 4.2.0-42-generic #49~14.04.1-Ubuntu SMP; stap --version says: "Systemtap translator/driver (version 2.3/0.158, Debian version 2.3-1ubuntu1.4 (trusty))"
So I first tried getting a…
sdaau
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How to split a systemtap script into multiple files?
I'm writing a medium-sized systemtap script with clearly separable parts. I would like to split it into multiple files. I see two possibilities for doing this, but not ideal. Is there an official way or maybe a convention?
1. concatenate manually…
Georg Schölly
- 124,188
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1 answer
How to get the host name of kill signal sender in systemtap script
all,
I encounter a problem when use systemtap script.
I don't know how to get the host name of kill signal sender in systemtap script.
for example. I am execute kill -9 xclock_process_pid in server 'sf1'. at the same time, I run 1.stap -x…
user1102185
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1 answer
systemtap user string copy fault
I have written a systemtap script to profile a C++ program. In the systemtap script I want to extract a class member.
Here is the c++ class definition:
class CFldOrder
{
public:
ByteArray cust_no;
};
class ByteArray
{
public:
const char*…
0
votes
1 answer
How can I send data on network inside a systemtap script?
I'm using systemtap to monitor some network, locking, task-wake-ups statistics, and I'd like to find an alternative to "println" (stap instruction), that would allow me to send data to a remote (networked) target (the idea being avoiding all disk…
Touisteur EmporteUneVache
- 111
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1 answer
How to interpret the output from Systemtap's futexes.stp
I am trying to find the lock contention in my code and I found the futexes.stp in the standard systemtap release. But I have a couple of questions with the output:
stap -d /usr/local/bin/cruncher ~/futexes.stp
(and then I run cruncher application in…
Junping
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1 answer
Convert debugging symbols to files and line numbers
I am using strace and SystemTap to obtain stack traces at system calls. What I get currently shows the function name but not the file name and line number. A trace from strace on ls using -k option:
> /usr/lib64/libc-2.22.so(_IO_file_close+0xb)…
r.v
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systemtap : Able to access local variables but cannot access local pointers
I have a dumb question,
I wanted to understand the source code flow with the help of system tap, for this i was trying to access a local variable using kernel.statement probe function, it displays all the other variable except pointers.
probe…
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1 answer
How can I probe file open and close at VFS using SystemTap
I seen example of SystemTap script using probe syscall.open.return { }
But there are some application doesn't call systemcall
So how can I probe file open at VFS
SilverIce
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