multibyte performance

I did some benchmarking with/without multibyte support using current.

(1) regression test

With multibyte support:
9.52user 3.38system 0:59.27elapsed 21%CPU (0avgtext+0avgdata  0maxresident)k

Without multibyte support:
8.97user 4.84system 1:00.85elapsed 22%CPU (0avgtext+0avgdata  0maxresident)k

(2) pgbench

With multibyte support(first column is the concurrent user, second is
the TPS):

1 46.004932
2 70.848123
4 88.147471
8 90.472970
16 96.620166
32 95.947363
64 92.718780
128 61.725883

Witout multibyte support:
1 52.668169
2 68.132654
4 79.956663
8 81.133516
16 96.618124
32 92.283645
64 86.936559
128 87.584099

for your convenience, a graph is attached(bench.png).

(3) testing environment

Linux kernel 2.2.17
PIII 750MHz, 256MB RAM, IDE disk
configure option: configure --enable-multibyte=EUC_JP or configure
postgresql.conf settings(other than default):    max_connections = 128    shared_buffers = 1024    wal_sync_method =
open_sync   deadlock_timeout = 100000
 
pgbench options:-s 2 (initialization)-t 10 (benchmarking)
--
Tatsuo Ishii