Speed up SuperPMI mcs -removeDup
#33939
Closed
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Create a "Hash" class that encapsulates the MD5 hashing that is
used to determine if two MCs are equivalent. Primarily, this
allows caching the Windows Crypto provider, which it is very slow
to acquire.
In addition, make some changes to avoid unnecessary memory allocations
and other unnecessary work.
The result is that
mcs -removeDup
is about 4x faster.Much of the remaining cost is that we read, deserialize the MC,
then reserialize the MC (if unique), and finally destroy the in-memory MC.
There is a lot of memory allocation/deallocation in this process that
could possibly be avoided or improved for this scenario.