Re: QShell performance

[mlazarus <mlazarus@xxxxxxxx>]

Diego,

 It's set to *LOCAL.  The first address is a local address and PINGs 
quickly.  The second address might be blocked by the firewall.

1) Does QShell require a valid route?

2) The second address should not be accessed since the first address is 
valid, correct?

 -mark

On 6/20/2017 10:43 PM, Diego Kesselman wrote:
> Mark,
>
> on CFGTCP option 12, are you pointing to *REMOTE or *LOCAL ? Have you 
> checked DNS entry and IP address is OK?
>
> Regards
>
> Diego Kesselman
>
>
> El 20/06/17 a las 21:39, mlazarus escribió:
> > Diego,
> >
> >  Nothing fancy.  Single partition, Power 8, no VIOS, all internal DASD.
> >
> >  -mark
> >
> > On 6/20/2017 12:16 PM, Diego Kesselman wrote:
> > > Mark,
> > >
> > > Are you using internal DASD or SAN based disks?
> > > Are you using VIOS?
> > > Is this a low CPU power partition?
> > >
> > >
> > > El 20/06/17 a las 10:02, Scott Klement escribió:
> > > > Diego,
> > > >
> > > > What were you doing in QShell that didn't perform well when 
> > > > hostname was a mess?  I've seen this too, but it was under specific 
> > > > situations where a program connected to the local system via Java 
> > > > classes.
> > > >
> > > > You might think "it's the local system, why would networking even 
> > > > apply" -- it applies because it's necessary to connect to network 
> > > > servers to do things like call native programs, run SQL, etc. Java 
> > > > (and probably other things as well) tries to determine the 
> > > > appropriate IP address to connect to by asking what the local 
> > > > hostname is, then doing an IP address lookup on that name.  If that 
> > > > name isn't in the hosts table, then it'll try a DNS server. If the 
> > > > DNS server is slow, this can add a huge overhead. Likewise, if 
> > > > there are multiple DNS servers and one is timing out, it can add a 
> > > > huge overhead.  IBM has run into this many times, so one of the 
> > > > first things they look for is to make sure your local host name is 
> > > > in the hosts file so this doesn't happen.
> > > >
> > > > But, what Mark is doing doesn't use those network servers. He's 
> > > > running native C code that directly runs on the local system.
> > > >
> > > >
> > > >
> > > >
> > > > On 6/20/2017 9:30 AM, Diego Kesselman wrote:
> > > > > Skott,
> > > > >
> > > > > I've experienced slow response in QSHELL when hostname is a mess.
> > > > >
> > > > > Mark,
> > > > >
> > > > > Do you have any DNS configuration ? (CFGTCP -> Option 12) If so, 
> > > > > are you using *LOCAL or *REMOTE ?
> > > > >
> > > > > Do you have an entry on host tables for FQDN (hostname + domain 
> > > > > name) and hostname ?
> > > > >
> > > > > Regards
> > > > >
> > > > > Diego Kesselman
> > > > >
> > > > >
> > > > > El 20/06/17 a las 09:15, Scott Klement escribió:
> > > > > > Mark,
> > > > > >
> > > > > > I must admit, I don't see what Diego's suggestion has to do with 
> > > > > > what you are doing... his suggestion is more related to Java 
> > > > > > programs being able to detect and connect to the local system -- 
> > > > > > which is known to perform slowly if you don't have the local host 
> > > > > > name in your hosts table. But, has nothing to do with your shell 
> > > > > > script.
> > > > > >
> > > > > > But, I'm really shocked at the result... 15 seconds to run 
> > > > > > 'hostname'?! Seriously?  This is just a simple program that 
> > > > > > retrieve's the system's hostname from memory and prints it. 
> > > > > > Shouldn't even take 1 second on a slow system.
> > > > > >
> > > > > > Something is very wrong.
> > > > > >
> > > > > > -SK
> > > > > >
> > > > > >
> > > > > > On 6/19/2017 9:53 PM, mlazarus wrote:
> > > > > > > Diego,
> > > > > > >
> > > > > > >   hostname took about 15 seconds.  java -version took about 50 
> > > > > > > seconds.
> > > > > > >
> > > > > > >   -mark