Re: [Haskell-cafe] Weird and entirely random problem...

That works, yes... thanks! On Wed, Jun 10, 2009 at 12:58 PM, Neil Brown wrote:

Hi,

I'm presuming the problem with your result is that the "

I took a look at the code, here's my thoughts on why this occurs.  If you start by putting something in the cache with key "foo", an entry is created in the times map, say: fromList [(0, "foo")].  If you then get the item from the cache, you add another item to the times map, giving you: fromList [(0, "foo"), (1, "foo")].  Another get operation, and you'll have fromList [(0, "foo"), (1, "foo"), (2, "foo")].  If you now call free on the cache, it finds the value associated with the minimum key: "foo".  But it only deletes the minimum key in the times map, leaving: fromList [(1, "foo"), (2, "foo")].  Thus you can have entries in the times map without them being in the store.  put would clear them out (perhaps this was the self-correction you saw), but get adds one each item, and free only clears one.  So you either need to fix get, or free.

Does that help, or was your question something else entirely? :-)

BTW, IntMap.fromList . filter (f . snd) . IntMap.toList is more concisely (and efficiently) written as: IntMap.filter f

Thanks,

Neil.

Jeff Heard wrote:

...

The code that causes it is here:

http://hpaste.org/fastcgi/hpaste.fcgi/view?id=5731#a5731

This is the strangest thing.  Occasionally, using nothing but gets and puts and frees on a non-full Cache will result in this:

Cache {      store = fromList        [("(\"icons/addBookmark.png\",False)",TextureObject {textureID = 4})        ,("(\"icons/addCircle.png\",False)",TextureObject {textureID = 1})        ,("(\"icons/addContent.png\",False)",TextureObject {textureID = 2})        ,("(\"icons/addElsewhereLink.png\",False)",TextureObject {textureID = 3})]    , times = fromList        [(61314,"(\"<span font_desc='sans 8'>294.0</span>\",AlignLeft,Nothing,WrapWholeWords,False,0.0,0.0)")

 ,(61316,"(\"icons/addBookmark.png\",False)"),(61318,"(\"icons/addCircle.png\",False)")

 ,(61320,"(\"icons/addContent.png\",False)"),(61322,"(\"icons/addElsewhereLink.png\",False)")]

   , now = 61323    , maxsize = 1024768000    , size = 4    , decimation = 0 }

Sometimes the problem is self-correcting.  Sometimes it is most certainly not.  But I don't understand how my code can possibly allow for this. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe