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May
10
comment Clarification about Linux TCP window size and delays
Application-layer acknowledgements would have solved this problem tool (by getting the ACKs back faster) and that wouldn't require any system-level tuning. (If you can always tune the systems this software runs on, then this is simpler. But if you can't, you should add application-layer acknowledgements.) Nice detective work, by the way.
May
9
comment How do I limit MS SQL Server memory usage?
@wfault: "By default, SQL Server can change its memory requirements dynamically based on available system resources." Many people like to mess with things just for the sake of messing with them, but what they're actually doing is inhibiting the server's ability to tune itself to changing load. If it ain't broke, you can't fix it. This is most commonly done by people who like to see lots of free memory to make themselves feel good, but actually, any memory that's free is also unused -- that is, wasted.
May
9
comment How do I limit MS SQL Server memory usage?
"Bargaining room"? Most likely, you should just leave things alone. The people who designed these things knew what they were doing, and unless you know something they don't, their decisions are probably best. Remember, any free memory is forever wasted. It's not like if you use half your memory today you can use twice your memory tomorrow.
May
9
answered Can I use address space from one Internet Registry in the region of another?
May
9
comment Why is SSH insisting on letting me log in?
Pass the -v flag to ssh and it will tell you why it let you in. Presumably, it let you in because it recognized your key.
May
9
comment Full direct bi-directional data swap between two storage volumes?
@JosephKern: That's not a bad idea. It sounds a lot safer.
May
9
revised Full direct bi-directional data swap between two storage volumes?
added 3 characters in body
May
9
answered Full direct bi-directional data swap between two storage volumes?
May
8
revised Clarification about Linux TCP window size and delays
deleted 1 characters in body
May
8
revised Clarification about Linux TCP window size and delays
added 588 characters in body
May
8
comment Changed SSHD port in VPS can't login
Unfortunately, it's also quite possible that some tools interpreted it as octal and some didn't. So the firewall and the daemon may not agree on the port. :(
May
8
revised Clarification about Linux TCP window size and delays
added 302 characters in body
May
8
comment Clarification about Linux TCP window size and delays
It's not clear that means the messages are aggregated into a single call to write or send. However, if they are, then the problem is probably in the design of the protocol layered on top of TCP -- most likely the absence of application-layer acknowledgements. These give ACKs packets to piggy back on and are essential for low-latency applications. (Answer updated.)
May
8
comment Changed SSHD port in VPS can't login
Are you sure you changed both the firewall and the daemon?
May
8
comment Clarification about Linux TCP window size and delays
There most certainly is. If you issue a small write when there's other data you want to send immediately, you are senselessly delaying the data you didn't include in the small write. (As the OP's problem demonstrates.)
May
8
answered Isn't it a bug to receive mail already containing a Delivered-To: <myaddress> header?
May
8
comment DD-WRT Block all but one site
Are you talking about allowing the router itself to talk to the web page or machines behind it? Because if you mean machines behind it, there's no rule to allow the packets that establish the connection in the first place into the router.
May
8
comment Wireless internet router keeps dropping out
It is not possible to have N without WMM. Also, you don't really explain the problem in any detail. For example, for nodes that can't reach the Internet, can they reach the router? Does DNS work for them?
May
8
comment Amazon RDS: What are IO Requests?
It is an amazing thing how easily we humans can accidentally make computers do absurdly huge amounts of work. You always have to go back and measure to make sure you didn't inadvertently compel the machine to do something astoundingly stupid. (I once improved the performance of a deployed real-world system by 40% in less than ten minutes (not counting the time to set up a profiled build) by adding one & to its code. Clearly, nobody had ever profiled it.)
May
8
comment show my public ssh keys, a good idea?
Unless there's some specific reason you don't want anyone to know that a particular public key is yours, there's no reason to keep them secret. (For example, one reason might be if you have access to a very critical machine and fear a $5 wrench attack.)