User Guide To getting the best performance with ACEDB

> ### ACEDB Version 4_8

> # User Guide To getting the best performance with ACEDB

> ## Background

>     Subject: Re:  how to make acedb fly

>     most important is to run the aceserver on a LOCAL disk
>     not nfs mounted and not on a RAID

>     actually LINUX gives impressive results because of its
>     excellent disk caching

>     =====

>     now aceperl is memory intensive and best is to run it on a
>     separate machine so you do not swap out aceserver
>     swapping bits of aceperl is ok, this just slws down some clients

>     ======

>     reading a big acefile is done in chuncks and should not too much degrade the
>     system

>     the worst case is some sort of queries

>     what i recommend for higehr performances is to index
>     as many tags as possible
>     my most recent code indexes all tags, that costs just a couple of Mb of ram
>     for the worm database and accelerates many requests

>     ====

>     no task is really cpu intensive, we are really io bound
>     so best is to have very fast disk, and a large ram, like 512 M
>     so the disks are really cached in ram

>     ====

>     i can send you the indexing fix for ace.4_7 if you wish
>     just 2 lines to edit in wnq/bindex.c than read-models

>     static void bIndexRegisterSecondaryTag(OBJ obj, int cc, BS bs, KEY masterTag)
>     {
>       if(!bs) return ;
>       if (bs->key == _UNIQUE)
>         { bIndexRegisterSecondaryTag(obj, cc, bs->right, masterTag) ; return ; }
>       if (bs->key == _XREF && bs->right)
>         { bIndexRegisterSecondaryTag(obj, cc, bs->right->right, masterTag) ; return ;}
>       if (class(bs->key) ||
>           bs->key < _Date)
>         return ;    /* break on values */
>       if (bs->down)
>         bIndexRegisterSecondaryTag(obj, cc, bs->down, masterTag) ;
>       /* no condition, just index every tag */
>       masterTag = bs->key ;

>     the fix is to remove the if which used to condition the line
>       masterTag = bs->key ;

>     then read-models -index // forces reindexing

> ### ACEDB Version 4_8

> Last modified: Tue Feb 6 13:21:35 GMT 2001