On Wed, Feb 26, 2014 at 5:50 PM, Norbert Hartl <norb...@hartl.name> wrote:
> > Am 26.02.2014 um 21:37 schrieb Mariano Martinez Peck < > marianop...@gmail.com>: > > > > > On Wed, Feb 26, 2014 at 5:30 PM, Norbert Hartl <norb...@hartl.name> wrote: > >> >> Am 26.02.2014 um 21:21 schrieb Mariano Martinez Peck < >> marianop...@gmail.com>: >> >> >> >> >> On Wed, Feb 26, 2014 at 3:53 PM, Norbert Hartl <norb...@hartl.name>wrote: >> >>> >>> Am 26.02.2014 um 14:38 schrieb Mariano Martinez Peck < >>> marianop...@gmail.com>: >>> >>> Just be careful 2: "I switched one of my servers to dump to stack with >>> fuel to disk if an exception occurs. " >>> Once it happened to me the stack I was taking for serializing an error >>> was too big. Too big because it even reached the UI. The UI has lots of >>> sensible objects that change quite frequently. So my graph to serialize was >>> big and the graph changed quite frequently. Result: Fuel throwing error >>> because the graph to serialize changed while being serialized. >>> Oh...exception? Fuel out exception! exception. Oh exception? ... >>> >>> Good point, thanks! >>> >>> So yeah..the fact that Fuel was throwing an error causes a loop so be >>> careful of that as well. >>> >>> If the serialization fails I just consider it an unrecoverable error and >>> proceed. I will add a logging message for that case so I can at least so >>> when something does not working while fueling out the stack. >>> >>> >> Forgot... "just be careful 3": it may happen that you cannot correctly >> *materialize >> (not serialization)* the graph: a method has changed, a class is >> missing..whatever... So what I did in the fuel out of failure tests is to >> add to the serializer header all the info (as plain strings) that we >> normally have in the PharoDebug.log. This "header" will always be able to >> be materialized.... this way, I don't have the risk of not being able to >> materialize and hence loose info, and yet I don't need PharoDebug.log as >> well. If you don't do what I did, then you likely need also pharoDebug.log >> just in case... >> >> That is unlikely to happen. My workflow is that every deployed image goes >> through the CI server. If a problem arises I download that same image from >> the CI server and load the stacks back into this. Everything is else is >> IMHO asking for trouble because contexts won't map properly. >> >> > > +9999. That's the safest thing to do: use an image with the same "code" as > the one that failed. > > >> I recommend everyone interested in this topic to take a look to: >> #serializeTestFailureContext:toFileNamed: >> >> That is what I am using because it does what I want to happen. It is only >> the selector that doesn't fit that well :) >> >> thanks a lot for this information Mariano. This is highly appreciated to >> get infos from someone that knows the stuff. >> >> > No problem. > > Just be careful 4: do not trust 100% of the ability to debug a post > morten. It should be considered "just as another extra tool to the > PharoDebug.log". But debugging a stack with Fuel could even be different > than the scenario that caused the error. Imagine class variables that > changed value, files/socktets or something that depended on external > resources, etc etc etc. What I mean is...the debug of a materialized fuel > stack may not be the same as debugging the error at the exact time it was > produced in the very same image it happened. But it is a great addition to > PharoDebug.log for several use cases where it helps anyway. > > Mariano, I admire your ability to offer all the precautions someone can > think of. > Because I've been there in this case ;) > Maybe it is because it involves a tool you did on your own. Thanks for > that. But for me the choice is easy. Having a fueled out stack is soooo > much better than textual log files so that I need to come up with a lot of > drawbacks until it wouldn't be worth using that. > +9999. That's why I recommend everybody to use this approach taking the necessary precautions. It does not harm at all and likely help a lot. > The side effects of having shared state is nothing that fuel introduces. > If you get a debugger in your image and go back a few frames/contexts/time > you cannot see the content of the objects at that time because they could > have changed. > indeed...that's why I said "in the exact time it was produced.." > I would wish, too, we would have a debugger that snapshots all state and > is able to "really" go back. But at the moment we don't have it. So it is > nothing fuel can solve. Fuel is just a wonderful tool that is capable of > making stupid tasks less stupid to handle. > > Completrly agree!!! nice quote btw! > thanks again :) > > No problem. You know that serializing/materializing a debugger was one of the coolest things I ever did. I was on my table, at Douai, thinking about examples to present Fuel in the ESUG Awards 2011. I remember my wife was sit in the couch and I said "Flor...what if I serialize the debugger!!!" . It took me 5 minutes to try it. I was sure it was going to fail...couldn't be so good for the first time. And surprisly....it worked out of the box. I couldn't believe it. I said...."ok...I have everything I need for ESUG" :) So yes, I very much like this feature! Also...it was the topic people outside the Smalltalk community commented the most about Fuel... of course...this is not just Fuel...it is Smalltalk that has contexts reified as objects and all it meta capabilities! Norbert > > > > Best, > > >> Norbert >> >> Cheers, >> >> >> >>> thanks, >>> >>> Norbert >>> >>> >>> >>> On Wed, Feb 26, 2014 at 10:28 AM, Norbert Hartl <norb...@hartl.name>wrote: >>> >>>> >>>> Am 26.02.2014 um 14:19 schrieb Max Leske <maxle...@gmail.com>: >>>> >>>> > Cool! :) >>>> > >>>> > Just be careful: if you're using a large model the stack can blow up >>>> your image with a low space warning / make it inresponsive (because the >>>> stack referenes your model and boom, pretty much all of your instances will >>>> becom serialized). >>>> > >>>> Yes, I know. But that would be a problem anyway. I think I have time. >>>> In the fuel files are 8 (!) contexts. :) >>>> >>>> Norbert >>>> >>>> > FYI we're actively working on pruning of the serialization graph to >>>> solve this. >>>> > >>>> > Max >>>> > >>>> > >>>> > On 26.02.2014, at 14:01, Norbert Hartl <norb...@hartl.name> wrote: >>>> > >>>> >> The best smalltalk/pharo moments you get if you try things you want >>>> to have just in order to see they are already there. >>>> >> >>>> >> Today FileBrowser. >>>> >> I switched one of my servers to dump to stack with fuel to disk if >>>> an exception occurs. Today I copied the files from the server to my local >>>> machine and opened a workspace starting to write an expression to open >>>> them. Then I thought it would be cool if I could use the file browser for >>>> it. So I opened it and navigated to the directory with the fuel files...et >>>> voilà...as soon as I clicked on a fuel file a button "materialize" appeared >>>> which showed the stack from the server right away. >>>> >> >>>> >> Just brilliant! Well done! >>>> >> >>>> >> Norbert >>>> > >>>> > >>>> >>>> >>>> >>> >>> >>> -- >>> Mariano >>> http://marianopeck.wordpress.com >>> >>> >>> >> >> >> -- >> Mariano >> http://marianopeck.wordpress.com >> >> >> > > > -- > Mariano > http://marianopeck.wordpress.com > > > -- Mariano http://marianopeck.wordpress.com
