2.10BSD

2.10BSD is a release of UNIX for the PDP-11 by a consortium of CSRG and the USENIX Association. It ran on all PDP-11 models with memory management. It was basically the same as 4.3BSD for the VAX, to the point where there were no separate manuals, users were expected to just use the 4.3BSD ones.

Some of the things that were added were:

• Conversion of the entire system to a 4.3BSD structure, including
  • 4.3BSD system calls
• inode, main memory, and swap caching
• 22-bit QBUS support
• RAM disk
• MSCP device driver (UDA50, KLESI, etc)
• 4.3BSD user software (libraries and applications)

As a result of the efficiency-related changes, it was the fastest PDP-11 Unix. As an example, in a PDP-11/44 with 4M of memory being in a student environment, it essentially never swapped, and only rarely did programs leave main memory.

An another benchmark, ULTRIX-11, V3.0, on a PDP-11/73 took 1.1 system seconds to start vi. 2.9BSD took approximately .9 system seconds (the reduction probably being attributable 2.9BSD's use of vfork). Once 2.10BSD had the vi image in its main memory cache, it took only .2 system seconds to start it.

It did not support networking, but almost all the internal work to do so had been done (the later 2.11BSD, released shortly thereafter, did add networking support.)

External links

• 2.10BSD - 2.10BSD documentation at TUHS
  • Second Distribution of Berkeley PDP-11 Software for UNIX - announcement