The Struggle of JGit
#git #performance
JGit is a lightweight, pure Java library implementation of the Git version control system. But still not lighter than the original implementation written in C. The choice of the language is always important when considering performance aspects of your program. Hence, JGit struggles with:
• Not having mmap(), memcpy(a,b,20) and other useful kernel operations. Hope soon we'll see foreign memory access API to resolve this issue.
• Not having unsigned types in Java. unsigned char or unsigned long doesn't exist in Java. Unfortunately, project Valhalla's value types are not going to support unsigned types.
• Not having an efficient way to represent a SHA-1. A byte[20] in Java will cost an additional 16 bytes of memory, and be slower to access because the bytes themselves are in a different area of memory from the container object.
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