SL> Hm... when I try to find a reasonable buffer size, I don't think SL> I would care much about SNMP_MAX_PDU_SIZE, but rather about the SL> EXPECTED traffic that I want the OS to buffer in times of SL> congestion, i.e. about what's a reasonable number of trap SL> (or request) PDUs to buffer, and what is the TYPICAL size.
What I wanted to say in my email was that the buffer should NEVER be less than MAX_PDU_SIZE. I tried to bring this up as a counterargument against using the default system buffer size (which could be in the "couple of K" ranges). The rationale behind this: I feel we shouldn't miss a perfectly legit packet when we are not in a bursting scenario... SL> If (server) SL> DEFAULT_BUFFER = SNMP_TYPICAL_PDU_SIZE * 200; Your formula is based on two empirical values. The definition of "TYPICAL" is probably "something that usually works". The 200 is probably based on your experience. The product of these two is "something that usually works based on your experience" ;-) SL> if (SNMP_MAX_PDU_SIZE > DEFAULT_BUFFER) SL> DEFAULT_BUFFER = SNMP_MAX_PDU_SIZE; So why do you want to add this extra check ? I also have the feeling you seem to agree with the assumption that the DEFAULT_BUFFER should never be less than the MAX_PDU_SIZE ... so somehow you do seem to care about SNMP_MAX_PDU_SIZE in contrary to what you wrote earlier. Anyway, I think the discussion slowed down after it was felt it would be better to: "Use the system default buffer size and don't touch the UDP buffers, unless someone has it specified in the conf files". This gives a flexibility to the system administrators to set the UDP buffers the way they want it and gives corrective power in the snmpd.conf in case the default values are not good enough for the snmp apps. An incremental patch has been written for this behaviour (it also adds some compile time configure options for allowing a hardcoded minimal default buffer if needed) "http://sourceforge.net/tracker/index.php?func=detail&aid=1022787&group_id=1 2694&atid=312694" The latest status of this patch is "Pending" (I think because a consensus has not been reached yet) Cheers, -- Geert -----Original Message----- From: Simon Leinen [mailto:[EMAIL PROTECTED] Sent: Thursday, October 07, 2004 9:42 PM To: Geert De Peuter Cc: [EMAIL PROTECTED]; 'John Naylon' Subject: Re: default sock buffer size: what should it be? Geert De Peuter writes: > If (server) > DEFAULT_BUFFER = SNMP_MAX_PDU_SIZE * 2; > else > DEFAULT_BUFFER = SNMP_MAX_PDU_SIZE; As long as SNMP_MAX_PDU_SIZE is 65536, your formulas happen to yield reasonable results... but I would probably use something more along the lines of If (server) DEFAULT_BUFFER = SNMP_TYPICAL_PDU_SIZE * 200; or, if you want to make sure we can receive maximally large PDUs, If (server) { DEFAULT_BUFFER = SNMP_TYPICAL_PDU_SIZE * 200; if (SNMP_MAX_PDU_SIZE > DEFAULT_BUFFER) DEFAULT_BUFFER = SNMP_MAX_PDU_SIZE; -- Simon. ------------------------------------------------------- This SF.net email is sponsored by: IT Product Guide on ITManagersJournal Use IT products in your business? Tell us what you think of them. Give us Your Opinions, Get Free ThinkGeek Gift Certificates! Click to find out more http://productguide.itmanagersjournal.com/guidepromo.tmpl _______________________________________________ Net-snmp-coders mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/net-snmp-coders
