[erlang-questions] Creating a diagnostic memory dump of live erlang VM

[Vladimir Ralev]

That looks great. I will check it out.


On Wed, Feb 19, 2014 at 3:08 PM, Fred Hebert <mononcqc@REDACTED> wrote:

> You can access these with process_info(Pid, messages) for the mailbox and
> sys:get_state(Pid) for the state, respectively.
>
> I also suggest taking a look at recon (http://ferd.github.io/recon/) to
> do live debugging in a system.
>
> Regards,
> Fred.
>
> On 02/19, Vladimir Ralev wrote:
> > From what I've seen the crashdump doesn't really have any of the objects
> in
> > the memory. If I have a string stuck in some mailbox or even just state
> > inside a gen_server process, can I see it?
> >
> >
> > On Wed, Feb 19, 2014 at 7:20 AM, Geoff Cant <nem@REDACTED> wrote:
> >
> > > Provided you're prepared to take down the node, you can
> > > erlang:halt("crashdump") and you'll get a dump of memory, heaps,
> tables,
> > > ... - erl_crash.dump file.
> > >
> > > You can view this in a web browser with crashdump_viewer.
> > >
> > > Crashdump debugging is unfortunate, but extremely useful. I use it on
> all
> > > my production systems.
> > >
> > > -G
> > >
> > > > On 18/02/2014, at 16:00, Vladimir Ralev <vladimir.ralev@REDACTED>
> > > wrote:
> > > >
> > > > Hello all,
> > > >
> > > > As a Java developer I really miss being able to create a "heap dump"
> of
> > > a live Erlang VM where I can see the objects in each process and the
> > > current process stack variables/trace. I realise there is no java-like
> heap
> > > in Erlang but there are the processes, mailboxes, stacks, file handles,
> > > sockets, ets and so on.
> > > >
> > > > In Java we can also use query tools to search the heaps for specific
> > > identifying strings/numbers/timestamps to find a graph of related
> objects.
> > > You can go find objects by type or find the stack variables for given
> > > thread. It would be very useful for understanding the system in
> production
> > > and diagnose issues.
> > > >
> > > > Would it be possible to have something like this in Erlang or it is
> > > fundamentally not allowed?
> > > > _______________________________________________
> > > > erlang-questions mailing list
> > > > erlang-questions@REDACTED
> > > > http://erlang.org/mailman/listinfo/erlang-questions
> > >
>
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>
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