[squid-users] What bit per entry means?

Dear all:
       I have read Squid FAQ. I am trying

   to use Cache Digest. but I don't know what

   "bit per entry". Isn't it each entry just needs four hash function

    and needs to set four bit ? And why we need to add 7 to "number

   of bits in array"....

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16.4 How is the size of the Cache Digest in Squid determined?
Upon initialisation, the capacity is set to the number of objects that can
be (are) stored in the cache. Note that there are upper and lower limits
here.

An arbitrary constant, bits_per_entry (currently set to 5), is used to
calculate the size of the array using the following formula:

  number of bits in array = capacity * bits_per_entry + 7
                                                        ??????????????????

The size of the digest, in bytes, is therefore:
  digest size = int (number of bits in array / 8)
Received on Wed Apr 18 2001 - 06:58:39 MDT