[ccache] Temporary Files vs NFS

[DATACOM - Samuel Lucas]

Hi,

I'm considering using a shared cache over NFS, but I'm a bit concerned
about creating the temporary files over NFS. Wouldn't the network become
a performance bottleneck?

For one of my application, the times for a second run are:
- Disabled cache: 7min 25sec
- Local cache: 3min 32sec
- NFS Shared cache: 6min 44sec

Measuring network traffic with the NFS server for a second run I got
uploads (compiler -> server) 27Mb/s, 1.9 GB and downloads (server ->
compiler) 1Mb/s, 77MB.

If we allow temporary files in local machine, would it create all
temporary files (.i, etc) locally and then transfer in the network only
the hash, speeding up the process?

Thank you,

 - Samuel