I've either found a bug, a quirk, or I'm stupid, but I've been banging my head against this issue for two days now, and I finally at least isolated the cause.
I have a server that allows you to connect and make multiple queries on a single socket connection the main loop decides which function to call, the function prints data to the sock and once we return the main loop basically does print {$client} "__END__\n";
Apparently this is bad, and I've created a simple echoing client server pair which illustrate...
#!/idcom/bin/perl
use IO::Socket::INET;
use Time::HiRes qw( gettimeofday tv_interval );
use strict;
our $PORT = 9990;
if(fork) {
my $s = IO::Socket::INET->new( LocalPort => $PORT, Listen => 5, Re
+use => 1 );
my $c = $s->accept();
while(<$c>) {
print {$c} $_;
}
}
else {
sleep 1;
my $s = IO::Socket::INET->new( PeerAddr => 'localhost:'.$PORT );
for(1..5) {
my $t0 = [gettimeofday];
print {$s} "func=mbs_descriptive&type=&secid=313627KM2\n";
print "".<$s>;
print tv_interval( $t0, [gettimeofday] ),"\n";
}
}
When this runs all is great!
func=mbs_descriptive&type=&secid=313627KM2
0.000259
func=mbs_descriptive&type=&secid=313627KM2
5e-05
func=mbs_descriptive&type=&secid=313627KM2
4.3e-05
func=mbs_descriptive&type=&secid=313627KM2
4.2e-05
func=mbs_descriptive&type=&secid=313627KM2
4.2e-05
But if you change that print to the socket to be:
print {$s} "func=mbs_descriptive&type=";
print {$s} "&secid=313627KM2\n";
Then sadness and woe befall the code!
func=mbs_descriptive&type=&secid=313627KM2
0.000181
func=mbs_descriptive&type=&secid=313627KM2
0.040125
func=mbs_descriptive&type=&secid=313627KM2
0.04009
func=mbs_descriptive&type=&secid=313627KM2
0.039891
func=mbs_descriptive&type=&secid=313627KM2
0.040025
ARGH! The first call is fast, and every subsequent one has about .4s tacked on for fun, multiply that by 5000 and it starts to really add up. What am I missing here?
- Ant
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