It is well known that Google uses Perforce as its internal source management system (it has a source license). Niall Kennedy writes:
Google uses a company-wide Perforce depot with almost no developer branches. Each developer has their own NFS workspace readable by anyone in the company, including automated processes. An administrative process takes snapshots of each developer workspace including local development environments accessed over SSH. Files within these snapshots can be compared to checked-in data, encrypted, and archived.
Dan Bloch did a presentation at Perforce European User Conference, called “Performance and Database Locking at Large Perforce Sites”. It contains statistics on Google Perforce Depot, such as:
- More than 3000 users and 100Gb of metadata on one primary server;
- Hardware is an HP DL585 4-way Opteron with 128Gb of memory;
- Depot is on a NetApp filer;
- Metadata and journal on RAID-10 local disk;