4 ms·

If you're talking about the flame graphs, they're a fairly common feature of modern profilers. The oldest implementation I know of is at https://github.com/bren

If you're talking about the flame graphs, they're a fairly common feature of modern profilers. The oldest implementation I know of is at https://github.com/brendangregg/FlameGraph https://github.com/brendangregg/FlameGraph.

gnufx 8y ago
I've never understood why flame graphs are better than the normal presentation of inclusive and exclusive timings in performance tools, even if they're not "modern", but embody some decades' experience. Anyone care to explain?
- detaro 8y ago
  I'm far from a performance expert, but my impression is: It shows the call paths to the functions and what part each path took, that's not so obvious from the typical table. On the other hand, finding functions that are called quite a lot all over the place and add up is easier in the table, so it's not become useless.
  - gsteinb88 8y ago
    The latter can be accomplished with inverted flame graphs (sometimes called icicle graphs) which show the call stack inverted
  - gnufx 8y ago
    Indeed, you want alternative views depending on what sort of profile or question about it you have -- with toggles in the GUI.
- andreareina 8y ago
  Flame graphs have extra information in the form of seeing the caller and callees. That, and I find the graphical presentation to be easier to scan.
  - gnufx 8y ago
    Of course I expect to see the call tree, and to flip between that and a flat view, to flip between different metrics in the views, and to see them across processes/threads. I'm talking about graphical tools (perhaps coupled with external reduction of the data) like CUBE [1], Paraprof [2], and those in toolsets like Open|Speedshop [3] and HPCToolkit [4] with which I'm less familiar. 1. http://www.scalasca.org/software/cube-4.x/documentation.html http://www.scalasca.org/software/cube-4.x/documentation.html 2. https://www.cs.uoregon.edu/research/tau/docs/newguide/bk01pt02.html https://www.cs.uoregon.edu/research/tau/docs/newguide/bk01pt... 3. https://openspeedshop.org https://openspeedshop.org 4. https://hpctoolkit.org https://hpctoolkit.org
kevin_thibedeau 8y ago
This is the same script. The Rust code is just invoking Perl to generate it.

gnufx 8y ago

I've never understood why flame graphs are better than the normal presentation of inclusive and exclusive timings in performance tools, even if they're not "modern", but embody some decades' experience. Anyone care to explain?

detaro 8y ago
I'm far from a performance expert, but my impression is: It shows the call paths to the functions and what part each path took, that's not so obvious from the typical table. On the other hand, finding functions that are called quite a lot all over the place and add up is easier in the table, so it's not become useless.
- gsteinb88 8y ago
  The latter can be accomplished with inverted flame graphs (sometimes called icicle graphs) which show the call stack inverted
- gnufx 8y ago
  Indeed, you want alternative views depending on what sort of profile or question about it you have -- with toggles in the GUI.
andreareina 8y ago
Flame graphs have extra information in the form of seeing the caller and callees. That, and I find the graphical presentation to be easier to scan.
- gnufx 8y ago
  Of course I expect to see the call tree, and to flip between that and a flat view, to flip between different metrics in the views, and to see them across processes/threads. I'm talking about graphical tools (perhaps coupled with external reduction of the data) like CUBE [1], Paraprof [2], and those in toolsets like Open|Speedshop [3] and HPCToolkit [4] with which I'm less familiar. 1. http://www.scalasca.org/software/cube-4.x/documentation.html http://www.scalasca.org/software/cube-4.x/documentation.html 2. https://www.cs.uoregon.edu/research/tau/docs/newguide/bk01pt02.html https://www.cs.uoregon.edu/research/tau/docs/newguide/bk01pt... 3. https://openspeedshop.org https://openspeedshop.org 4. https://hpctoolkit.org https://hpctoolkit.org

kevin_thibedeau 8y ago

This is the same script. The Rust code is just invoking Perl to generate it.