The problem for me isn't the exception vs miss, it's data reliability. On Tue, Oct 5, 2010 at 10:19 AM, Keenan Brock <[email protected]> wrote:
> Hi Brandon, > > Once, I had changed my memcache client library and it started raising > exceptions. > Turns out the previous library just returned a nil, while this one raised > an exception. So I hacked the library to return nil on failures rather than > throw exceptions. > > (The previous library just returned a nil not failing) > > > This seems like the answer for me. > > Maybe alter the gem and add the option to throw an exception instead of > returning a nil. > > > But it is curious that it would fail so many times. > > --Keenan > > On Oct 5, 2010, at 9:25 AM, Brandon Casci wrote: > > It took a few days for the ticket to get answered, but yesterday did get > confirmation from Heroku that this was a problem, with Amazon EC2 causing > the pain. See this: > > > http://getsatisfaction.com/heroku/topics/sporadic_errors_with_memcache_addon > > I have the same symptoms they mention, though for my app it's not sporadic, > it's a state. The only way I can seem to shake it is by opening the rails > console and doing Rails.cache.clear, and things go back to normal until > problem kicks back up again. > > I'd rate this problem a 9.5 out of 10 for my app. > > What makes things particularly difficult for me is input comes in from > outside sources and sits in memcache. In this case, what a radio station is > currently playing, and it should stay there until the next time until new > data comes in via the API. I suppose it's fair to say that data should be > placed in the DB, which is fine. I can do that, and then do a > Rails.cache.fetch from there. Any miss would mean another AR query instead > of a nil. That's still a problem though, because a lot of supplementary data > gets queried with the song title, artwork, photos, products and more. So all > those cache misses will have a recognizable negative impact. > > > > > On Tue, Oct 5, 2010 at 9:13 AM, John Norman <[email protected]> wrote: > >> Brandon: Regretably, I'm cheating and am using the Dalli gem without the >> guidance of Heroku. :-( I couldn't get memcached-northscale to compile on my >> Mac. Whatever. >> >> In any case: >> >> >> Rails.cache.write "foo", "bar" >> => true >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> Rails.cache.read "foo" >> => "bar" >> >> >> >> On Mon, Oct 4, 2010 at 3:53 PM, Brandon Casci <[email protected]>wrote: >> >>> Yep :) >>> >>> >>> On Mon, Oct 4, 2010 at 4:48 PM, Teng Siong Ong <[email protected]>wrote: >>> >>>> are you sure that you are using the supported memcache gem? >>>> http://docs.heroku.com/memcache >>>> >>>> On Mon, Oct 4, 2010 at 3:43 PM, Brandon Casci >>>> <[email protected]>wrote: >>>> >>>>> It's crazy making. >>>>> >>>>> >> Rails.cache.read "mykey" >>>>> => nil >>>>> >> Rails.cache.read "mykey" >>>>> => nil >>>>> >> Rails.cache.read "mykey" >>>>> => nil >>>>> >> Rails.cache.read "mykey" >>>>> => 1 >>>>> >> Rails.cache.read "mykey" >>>>> => nil >>>>> >> Rails.cache.read "mykey" >>>>> => nil >>>>> >> Rails.cache.read "mykey" >>>>> => 1 >>>>> >> Rails.cache.read "mykey" >>>>> => nil >>>>> >> Rails.cache.read "mykey" >>>>> => nil >>>>> >>>>> >>>>> On Sat, Oct 2, 2010 at 7:58 PM, Brandon Casci >>>>> <[email protected]>wrote: >>>>> >>>>>> Hello >>>>>> >>>>>> I'm new to Heroku, so I'm not sure if this is a problem, or normal >>>>>> behavior. >>>>>> >>>>>> I'm seeing a inconsistent memcache reads. Reading a key will sometimes >>>>>> alternate between nil and the value placed in memcache. Other times the >>>>>> value just seems to vanish, though that could be a sign that memcache is >>>>>> full, though I can't find a way to tell if it's full. >>>>>> >>>>>> What do es everyone think might be happening? >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> ========================================= >>>>>> Brandon Casci >>>>>> Loudcaster >>>>>> http://loudcaster.com >>>>>> ========================================= >>>>>> >>>>> >>>>> >>>>> >>>>> -- >>>>> ========================================= >>>>> Brandon Casci >>>>> Loudcaster >>>>> http://loudcaster.com >>>>> ========================================= >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "Heroku" group. >>>>> To post to this group, send email to [email protected]. >>>>> To unsubscribe from this group, send email to >>>>> [email protected]<heroku%[email protected]> >>>>> . >>>>> For more options, visit this group at >>>>> http://groups.google.com/group/heroku?hl=en. >>>>> >>>> >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Heroku" group. >>>> To post to this group, send email to [email protected]. >>>> To unsubscribe from this group, send email to >>>> [email protected]<heroku%[email protected]> >>>> . >>>> For more options, visit this group at >>>> http://groups.google.com/group/heroku?hl=en. >>>> >>> >>> >>> >>> -- >>> ========================================= >>> Brandon Casci >>> Loudcaster >>> http://loudcaster.com >>> ========================================= >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "Heroku" group. >>> To post to this group, send email to [email protected]. >>> To unsubscribe from this group, send email to >>> [email protected]<heroku%[email protected]> >>> . >>> For more options, visit this group at >>> http://groups.google.com/group/heroku?hl=en. >>> >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Heroku" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]<heroku%[email protected]> >> . >> For more options, visit this group at >> http://groups.google.com/group/heroku?hl=en. >> > > > > -- > ========================================= > Brandon Casci > Loudcaster > http://loudcaster.com > ========================================= > > -- > You received this message because you are subscribed to the Google Groups > "Heroku" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/heroku?hl=en. > > > -- > You received this message because you are subscribed to the Google Groups > "Heroku" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]<heroku%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/heroku?hl=en. > -- ========================================= Brandon Casci Loudcaster http://loudcaster.com ========================================= -- You received this message because you are subscribed to the Google Groups "Heroku" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
