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Shouldn't this be failure caching? From the article, it seems it doesn't refer to a cache failure, but rather, a failure cached... Evercat 02:48 26 May 2003 (UTC)
Seems like it is a correct lingo among hackers. http://mail.python.org/pipermail/python-list/2001-November/071275.html
I too have never heard of it, so maybe I am wrong. As you see, I just cut and pasted.
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Taku 02:56 26 May 2003 (UTC)
Have had exactly this, notably by caching connection strings in the COM+ Shared Property Manager (SPM). Problem is, after a DTC restart or package shutdown, the SPM corrupts / truncates entries stored in it (but doesn't delete the entry entirely). So next time we need a connection string, we pull out the corrupted one from cache. Resolution is to e.g. add a second entry in the cache, the second verifying the first (e.g. a MD5 hash or similar) - this way cache corruption can be detected and refreshed ... Not sure this is really antipattern ... ? (nonnb)
I agree with others who have stated that "caching failure" is a bad name for this article, as it is very ambiguous. "Caching failure" can be interpreted as if there was a process, caching, that had a failure. And yet, it can also be interpreted as a cache miss, when the cache failed to return a result and it has to be looked up from the original - while actually it's a cache hit, which is merely incoherent.
In the context of DNS, the term "negative cache" is typically used. "Failure cache" or "failure caching" also sounds more obvious than "caching failure". The lead section currently also states that it's a bug — while very often software might cache failures by design. -- intgr 11:15, 6 December 2006 (UTC)
I think this passage may be incorrect:
For instance, DNS requires that caching nameservers remember negative responses as well as positive ones. If an authoritative nameserver returns a negative response, indicating that a name does not exist, this is cached.
RFC 2182 (section 3.3) says "While positive DNS results are usually cached, the lack of a result is not cached." This is in regards to a nameserver's unreachability, though, not a response from a nameserver indicating a domain does not exist. So I'm not sure the above extract from the article is wrong. Perhaps sources/clarification could be added? -- Pheelineerie ( talk) 19:47, 5 March 2014 (UTC)
effective algorithms for negative caches?
![]() | This article is rated Stub-class on Wikipedia's
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Shouldn't this be failure caching? From the article, it seems it doesn't refer to a cache failure, but rather, a failure cached... Evercat 02:48 26 May 2003 (UTC)
Seems like it is a correct lingo among hackers. http://mail.python.org/pipermail/python-list/2001-November/071275.html
I too have never heard of it, so maybe I am wrong. As you see, I just cut and pasted.
--
Taku 02:56 26 May 2003 (UTC)
Have had exactly this, notably by caching connection strings in the COM+ Shared Property Manager (SPM). Problem is, after a DTC restart or package shutdown, the SPM corrupts / truncates entries stored in it (but doesn't delete the entry entirely). So next time we need a connection string, we pull out the corrupted one from cache. Resolution is to e.g. add a second entry in the cache, the second verifying the first (e.g. a MD5 hash or similar) - this way cache corruption can be detected and refreshed ... Not sure this is really antipattern ... ? (nonnb)
I agree with others who have stated that "caching failure" is a bad name for this article, as it is very ambiguous. "Caching failure" can be interpreted as if there was a process, caching, that had a failure. And yet, it can also be interpreted as a cache miss, when the cache failed to return a result and it has to be looked up from the original - while actually it's a cache hit, which is merely incoherent.
In the context of DNS, the term "negative cache" is typically used. "Failure cache" or "failure caching" also sounds more obvious than "caching failure". The lead section currently also states that it's a bug — while very often software might cache failures by design. -- intgr 11:15, 6 December 2006 (UTC)
I think this passage may be incorrect:
For instance, DNS requires that caching nameservers remember negative responses as well as positive ones. If an authoritative nameserver returns a negative response, indicating that a name does not exist, this is cached.
RFC 2182 (section 3.3) says "While positive DNS results are usually cached, the lack of a result is not cached." This is in regards to a nameserver's unreachability, though, not a response from a nameserver indicating a domain does not exist. So I'm not sure the above extract from the article is wrong. Perhaps sources/clarification could be added? -- Pheelineerie ( talk) 19:47, 5 March 2014 (UTC)
effective algorithms for negative caches?