• Arun Chandrasekaran (3/3) Feb 25 2020 Does anyone use Linux perf here, with D symbols demangled?
• Sebastiaan Koppe (3/6) Feb 26 2020 I vaguely remember using ddemangle
• drug (9/12) Feb 26 2020 If you use `perf report` then that currently is impossible I guess. But
• Mathias Lang (17/20) Feb 26 2020 For the non interactive version, you can just use `perf report |
• Alex Burton (49/52) Feb 26 2020 This is my sh script for performance monitoring on debian buster
• Arun Chandrasekaran (5/11) Feb 29 2020 These work-arounds work to some extent, but gets in the way too

Arun Chandrasekaran <aruncxy gmail.com> writes:

Does anyone use Linux perf here, with D symbols demangled?

I'm on Ubuntu 19.10, but I can't get perf to demangle the D 
symbols.

Sebastiaan Koppe <mail skoppe.eu> writes:

On Wednesday, 26 February 2020 at 07:20:03 UTC, Arun 
Chandrasekaran wrote:
 Does anyone use Linux perf here, with D symbols demangled?

 I'm on Ubuntu 19.10, but I can't get perf to demangle the D 
 symbols.

I vaguely remember using ddemangle

drug <drug2004 bk.ru> writes:

On 2/26/20 10:20 AM, Arun Chandrasekaran wrote:
 Does anyone use Linux perf here, with D symbols demangled?
 
 I'm on Ubuntu 19.10, but I can't get perf to demangle the D symbols.

If you use `perf report` then that currently is impossible I guess. But 
if you use flamegraph for example then ddemangle can help here:
```
git clone https://github.com/brendangregg/FlameGraph.git
perf script | FlameGraph/stackcollapse-perf.pl | 
FlameGraph/flamegraph.pl | ddemangle > perf.svg
```

but some symbols remain mangled

Mathias Lang <pro.mathias.lang gmail.com> writes:

On Wednesday, 26 February 2020 at 07:20:03 UTC, Arun 
Chandrasekaran wrote:
 Does anyone use Linux perf here, with D symbols demangled?

 I'm on Ubuntu 19.10, but I can't get perf to demangle the D 
 symbols.

For the non interactive version, you can just use `perf report | 
ddemangle`
As for the interactive version, I don't know. Other coreutils 
tools have a `--demangle=dlang` option (e.g. `nm`), but perf only 
have `--demangle` to prevent demangling of symbols:

```
         --demangle        Disable symbol demangling
         --demangle-kernel
                           Enable kernel symbol demangling
```

There's also an `objdump` option which you can set to a shell 
script that does `objdump --demangle=dlang $*` so you get symbols 
demangled in the disassembled code, but for the main interface, 
there doesn't seem to be a way to do it interactively. Perhaps 
raise the issue upstream?

Alex Burton <ab bab.com> writes:

On Wednesday, 26 February 2020 at 07:20:03 UTC, Arun 
Chandrasekaran wrote:
 Does anyone use Linux perf here, with D symbols demangled?

 I'm on Ubuntu 19.10, but I can't get perf to demangle the D 
 symbols.

This is my sh script for performance monitoring on debian buster 
using Brendan Greggs flamegraph:

sudo perf record -F 99 -a --call-graph dwarf -- sleep 10
#sudo perf record -F 99 --call-graph dwarf -p 31984
sudo perf script > tree.perf
~/dev/FlameGraph/stackcollapse-perf.pl tree.perf > tree.folded
~/dev/FlameGraph/flamegraph.pl tree.folded > tree_.svg
cat tree_.svg | ./dfilt > tree.svg
firefox tree.svg

This is the source code in dfilt:

import std.ascii : isAlphaNum;
import std.algorithm;
import std.range;
import std.conv : to;
import std.demangle : demangle;
import std.functional : pipe;
import std.stdio;



string translateSymbol(string s)
{
	if (s[0..2] == "_D")
	{
		auto result = demangle(s);
		writefln("%s => %s",s,result);
	}
	return s;
}

string translateGroup(U)(U group)
{
	if ((group[0]))
		return demangle(group[1].to!string);
	else
		return group[1].to!string;
}

auto translateLine(string l)
{
	return l.chunkBy!(a => isAlphaNum(a) || a == 
'_').map!translateGroup.joiner;
}

void main()
{
     auto result = stdin.byLineCopy
         .map!translateLine
         .joiner("\n").array;
		
	result.copy(stdout.lockingTextWriter);
}


Hope this helps

Arun Chandrasekaran <aruncxy gmail.com> writes:

On Wednesday, 26 February 2020 at 13:21:42 UTC, Alex Burton wrote:
 On Wednesday, 26 February 2020 at 07:20:03 UTC, Arun 
 Chandrasekaran wrote:
 [...]

 This is my sh script for performance monitoring on debian 
 buster using Brendan Greggs flamegraph:

 [...]

These work-arounds work to some extent, but gets in the way too 
often as (I'm just lazy). I will see if I can check with upstream 
to include ddemangle.

Thanks everyone.