Using gdb to explore a running image? Blog post or video format is great. Most of what I've run across is related to the internals of the VM rather than debugging an image. My gdb skills are pretty rusty plus I suspect that not knowing all of the helper functions available in the VM (and how to best use them in a debugging workflow) is slowing me down.
When possible you’re much better off using the VMSimulator to examine an image.
On 18-09-2017, at 4:25 PM, Phil B pbpublist@gmail.com wrote:
Using gdb to explore a running image? Blog post or video format is great. Most of what I've run across is related to the internals of the VM rather than debugging an image. My gdb skills are pretty rusty plus I suspect that not knowing all of the helper functions available in the VM (and how to best use them in a debugging workflow) is slowing me down.
tim -- tim Rowledge; tim@rowledge.org; http://www.rowledge.org/tim "Bother" said Pooh, as his rucksack opened whilst skydiving
On Mon, Sep 18, 2017 at 8:25 PM, Phil B pbpublist@gmail.com wrote:
Using gdb to explore a running image? Blog post or video format is great. Most of what I've run across is related to the internals of the VM rather than debugging an image. My gdb skills are pretty rusty plus I suspect that not knowing all of the helper functions available in the VM (and how to best use them in a debugging workflow) is slowing me down.
Long ago I wrote this: https://marianopeck.wordpress.com/2011/04/23/how-to-debug-the-vm/ Of course, it's still outdated but it may help you. It's very basic, thought.
There some other VM + gdb posts that may help you: https://marianopeck.wordpress.com/tag/gdb/
Cheers,
On Tue, Sep 19, 2017 at 1:25 AM, Phil B pbpublist@gmail.com wrote:
Using gdb to explore a running image? Blog post or video format is great. Most of what I've run across is related to the internals of the VM rather than debugging an image. My gdb skills are pretty rusty plus I suspect that not knowing all of the helper functions available in the VM (and how to best use them in a debugging workflow) is slowing me down.
I'm curious about your use case, that is, what problem are you actually trying to debug?
- Bert -
In short, I seem to have a knack for finding hard to debug issues.
1) I have an issue related to some parsers I'm working on re: large # of stack pages in use. Eliot provided some helpful tips a couple of months ago that really helped here. It turns out I had two different issues related to this, one resolved (thanks to the image side VM params he pointed me to) the other still outstanding (probably a deeper structural issue and I'm thinking that the easier way to debug it will be to dial back the stack pages and let it crash earlier). These are bugs in my code and not not the VM.
2) Under heavy load I'm having problems with Event Tickler spiking in CPU usage (50% or more) and the image becoming generally unresponsive. Event Tickler never seems to recover once in this state.
3) A variety of site-specific network socket issues. I think I've done about all I can in the image and need to start looking in the plugin but i suspect that's only going to be productive on live connections w/ gdb.
4) Generally needing to be able to more quickly troubleshoot plugin and FFI issues. My images are heavy users of both and I've run into a variety of edge cases where I segfault the VM.
Over time, I seem to keep running into issues like these so that's why I'm looking to improve my debugging skills at the VM/image boundary.
On Sep 19, 2017 8:12 AM, "Bert Freudenberg" bert@freudenbergs.de wrote:
On Tue, Sep 19, 2017 at 1:25 AM, Phil B pbpublist@gmail.com wrote:
Using gdb to explore a running image? Blog post or video format is great. Most of what I've run across is related to the internals of the VM rather than debugging an image. My gdb skills are pretty rusty plus I suspect that not knowing all of the helper functions available in the VM (and how to best use them in a debugging workflow) is slowing me down.
I'm curious about your use case, that is, what problem are you actually trying to debug?
- Bert -
vm-dev@lists.squeakfoundation.org
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Bert Freudenberg -
Mariano Martinez Peck -
Phil B -
tim Rowledge