Optimizing ReadLanguageWorkerFile to avoid LOH allocations by reading files in chunks

[kshyju]

Optimized RpcWorkerConfigFactory.ReadLanguageWorkerFile to avoid LOH allocations by reading worker executable files in buffered chunks instead of using File.ReadAllBytes. The previous implementation loaded entire files into memory, resulting in LOH allocations and increased GC pressure. Since the method's main purpose is to preload files into the OS disk cache, reading in chunks achieves this efficiently, reducing memory usage and minimizing the likelihood of blocking GEN2 garbage collections.

Visual Studio

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DotMemory

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With the previous approach, the 120MB+ LOH allocation would persist until the next Gen2 GC (blocking). Change in this PR reduces the likelihood of triggering a Gen2 GC by avoiding large object heap allocations.

Pull request checklist

IMPORTANT: Currently, changes must be backported to the in-proc branch to be included in Core Tools and non-Flex deployments.

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Additional information

Additional PR information

[safihamid]