Problem - export over named pipe on Solaris 2.3

Performance problem using export over named pipes.

The problem described below was fixed using patch 101647-02 available from SUN. I would recommend this patch if you intend to export database over named pipe to a tape. The patch description may be misleading as it suggests that the patch is designed for named pipes on NFS system while it improves performance for all named pipes applications.

Thanks to Time Read and Bruce Keane (SUN support) who suggested this solution.

Benchmark result after the patch was implemented:

real	5:57.2
user	4:23.7
sys	  35.6

Previous posting:

We are runnig Oracle 7.0.16.4 on Solaris 2.3 - SUN 1000 and SpacServer 10. We have performance problem with export writing over named pipe to Cybernetics CY-8505 tape drive.

The benchmarks are for 60 MB table.

1. Export to file system:

real	6:11.8
user	6:10.8
sys	  39.0

2. dd this file to tape:

real	2:14.3
user	   8.3
sys	  14.5

3. Write export output over named pipe to dd and the tape:

real	36:25.5
user	 7:16.0
sys	 2:58.1


Thanks,
						Edwin Kuprienko

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