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APAR (Authorized Program Analysis Report) |
Abstract
OSP-DB DNS LOOKUP DELAY FOR SQL CONNECT
Error Description
getnameinfo() done in QSQCONN in RWCNNATT expansion leading to
poor performance when DNS delays returning the host name.
Fix is to not do the getnameinfo() at *SET time but rather at
*RETRIEVE time for ?RWCNNATT.
This way the expense of the lookup isn't incurred everytime
QSQCONN is called, but rather when the user references
CLIENT_HOST.
Problem Summary
SQL Performance problem during connect due to getnameinfo() call
in QSQCONN exacerbated by poor performing DNS. This call is to
retrieve the built-in global variable CLIENT_HOST value.
Problem Conclusion
Remove getnameinfo() call from connect path (QSQCONN) and move
it into global variable path so that when CLIENT_HOST is
requested, the DNS lookup expense is incurred for those that use
the variable.
Temporary Fix
Comments
Circumvention
PTFs Available
Affected Modules
Affected Publications
Summary Information
Status............................................ | CLOSED PER |
HIPER........................................... | No |
Component.................................. | 5770SS1DB |
Failing Module.......................... | RCHMGR |
Reported Release................... | R720 |
Duplicate Of.............................. |
System i Support
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Document Information
Modified date:
30 May 2015