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diff --git a/vendor/github.com/golang/groupcache/README.md b/vendor/github.com/golang/groupcache/README.md deleted file mode 100644 index 70c29da16..000000000 --- a/vendor/github.com/golang/groupcache/README.md +++ /dev/null @@ -1,73 +0,0 @@ -# groupcache - -## Summary - -groupcache is a caching and cache-filling library, intended as a -replacement for memcached in many cases. - -For API docs and examples, see http://godoc.org/github.com/golang/groupcache - -## Comparison to memcached - -### **Like memcached**, groupcache: - - * shards by key to select which peer is responsible for that key - -### **Unlike memcached**, groupcache: - - * does not require running a separate set of servers, thus massively - reducing deployment/configuration pain. groupcache is a client - library as well as a server. It connects to its own peers. - - * comes with a cache filling mechanism. Whereas memcached just says - "Sorry, cache miss", often resulting in a thundering herd of - database (or whatever) loads from an unbounded number of clients - (which has resulted in several fun outages), groupcache coordinates - cache fills such that only one load in one process of an entire - replicated set of processes populates the cache, then multiplexes - the loaded value to all callers. - - * does not support versioned values. If key "foo" is value "bar", - key "foo" must always be "bar". There are neither cache expiration - times, nor explicit cache evictions. Thus there is also no CAS, - nor Increment/Decrement. This also means that groupcache.... - - * ... supports automatic mirroring of super-hot items to multiple - processes. This prevents memcached hot spotting where a machine's - CPU and/or NIC are overloaded by very popular keys/values. - - * is currently only available for Go. It's very unlikely that I - (bradfitz@) will port the code to any other language. - -## Loading process - -In a nutshell, a groupcache lookup of **Get("foo")** looks like: - -(On machine #5 of a set of N machines running the same code) - - 1. Is the value of "foo" in local memory because it's super hot? If so, use it. - - 2. Is the value of "foo" in local memory because peer #5 (the current - peer) is the owner of it? If so, use it. - - 3. Amongst all the peers in my set of N, am I the owner of the key - "foo"? (e.g. does it consistent hash to 5?) If so, load it. If - other callers come in, via the same process or via RPC requests - from peers, they block waiting for the load to finish and get the - same answer. If not, RPC to the peer that's the owner and get - the answer. If the RPC fails, just load it locally (still with - local dup suppression). - -## Users - -groupcache is in production use by dl.google.com (its original user), -parts of Blogger, parts of Google Code, parts of Google Fiber, parts -of Google production monitoring systems, etc. - -## Presentations - -See http://talks.golang.org/2013/oscon-dl.slide - -## Help - -Use the golang-nuts mailing list for any discussion or questions. |