RE: Informix 7 slow over WAN yet fast over LAN
In one of the later Informix odbc connects, there is an option to not pad varchars with zero's. By default , a varchar is returned with tons of padded zeros. Only patched very recently. On a LAN you would not notice the difference but over wan, a huge impact on traffic. José -----Original Message----- From: informix-list-bounces@iiug.org [mailto:informix-list-bounces@iiug.org] On Behalf Of WalidFahmy via DBMonster.com Sent: 2006-07-14 08:50 AM To: informix-list@iiug.org Subject: Re: Informix 7 slow over WAN yet fast over LAN Thanks Art. We eliminated the lookup issue and will test now changing the Buffer Size, re- writing the application is a nightmare. Regards Walid Art S. Kagel wrote: >> All, >> My Informix 7 Server peformance on the Local Area Network is very acceptable, >[quoted text clipped - 5 lines] >> Server and Client. >> Did anybody see this before ? Can anybody help ? > >Two possible causes not mentioned: > >1- You note an excess of ACKs, etc. This could be a symptom of the second >problem, but another may be the amount of data that's really needed versus >the comm buffer size. The buffers default to 4K (max 32K). You can >increase the buffer size with the environment variable FETBUFSIZE, set it to >2^15-1 (32767) in the client's environment to get a max sized buffer session >setup between the client and the server. This will decrease the number of >round trips by a factor of 8 which will help even if 2 is the larger problem. > >2- You application is poorly designed so that it is retrieving far more data >than it needs and filtering it in software. This will cause the application >to run inordinately slower across narrower/slower pipes like your WAN than >it does across a fast LAN. Examine the SQL and code to determine if the >filtering and the joins are optimal. > >Art S. Kagel -- Message posted via DBMonster.com http://www.dbmonster.com/Uwe/Forums.aspx/informix/200607/1 _______________________________________________ Informix-list mailing list Informix-list@iiug.org http://www.iiug.org/mailman/listinfo/informix-list