pnoe@dg13.cec.be (Pierre Noel) (10/18/90)
Hi NetLand, I made a program using socket protocols under TCP/IP Ethernet, to communicate with a Unix Server (in that case, SCO-ODT Unix on a Olivetti's XP9 with a 3COM's 3C503 Ethernet Card), I also made the Server part of the protocol then I can control both sides of the problem. My problem seems to be in the client side of the program : due to our site configuration, I gave two versions of the product, one for PC/TCP (Release 2.04) and the other for PC-NFS (Release 3.01). The main purpose of the application is to download lot of files (2/3 Mbytes each time) from the Server to the Client requesting them; the download is segmented, at the socket level, in records of 1024 bytes each, using the send() and recv() function calls. The sources of the PC/TCP and PC-NFS application are excactly the same, only the libraries linked to are different. I made test on the same machine (Olivetti M300 with a 3COM 3C501 Ethernet Card), the result is absolutely uncomprehensible : the relation between the time spent by the PC/TCP and the PC-NFS application is about 1 to 10 !!! I've checked where was the problem and what I've seen is that the difference of performance is located in the time spent between reception of records. I've also encountered the same kind of problem with PC-NFS when trying to rcp multiple small file one after another : the 2 firsts were transmitted ok but theother ones had also big delay. My question is : do someone has knowledge of similar problem and do you know if it is possible to tune the product to have acceptable performance ? I know that the solution is maybe changing all our PC-NFS to PC/TCP but as our park is about 700 PCs and our needs for the application are really urgent, it must not be the right solution now. I would be very happy to receive clues. Thank you for your attention and apologies for spelling mistakes Pierre Noel pnoe@dg13.cec.be