500 instances of tomcat on the same server

We can run 75 to 125 instances of tomcat on a single Linux server with 12 cores and 128GB RAM. It works great. CPU is around 25%, our JVMs are not throwing OOMEs, iowait is minimal, and network traffic is about 30Mbps. We're happy with the results. Now we're upping the ante. We have a 48-core s

RE: Re-Use TCP Source Ports if the Socket is Unique?

> -Original Message- > From: Mark H. Wood > Sent: Friday, June 25, 2021 12:30 PM > To: users@tomcat.apache.org > Subject: Re: Re-Use TCP Source Ports if the Socket is Unique? > > On Fri, Jun 25, 2021 at 12:46:03PM +, Eric Robinson wrote: > > Olaf and Scott -- > > > > Thanks to both of

RE: Re-Use TCP Source Ports if the Socket is Unique?

> -Original Message- > From: Christopher Schultz > Sent: Friday, June 25, 2021 11:33 AM > To: users@tomcat.apache.org > Subject: Re: Re-Use TCP Source Ports if the Socket is Unique? > > Eric, > > On 6/24/21 21:14, Eric Robinson wrote: > > I guess I may have answered this question for mysel

RE: Re-Use TCP Source Ports if the Socket is Unique?

> -Original Message- > From: Olaf Kock > Sent: Friday, June 25, 2021 8:07 AM > To: users@tomcat.apache.org > Subject: Re: Re-Use TCP Source Ports if the Socket is Unique? > > > On 25.06.21 14:46, Eric Robinson wrote: > > Olaf and Scott -- > > > > Thanks to both of you for your comments. I

DB Connection Pool Error Handling

Periodically, in an otherwise normal running system, I get one simple mySQL query/create/update that takes 25+ seconds.  I'm pursuing this with mySQL logs and other steps on the mySQL end. But I have a couple of questions related to the TC side.  I start and end a timer on each side of a statem

Re: Re-Use TCP Source Ports if the Socket is Unique?

On Fri, Jun 25, 2021 at 12:46:03PM +, Eric Robinson wrote: > Olaf and Scott -- > > Thanks to both of you for your comments. I may have asked my question poorly, > since what you both described is the way I understand TCP to work. There is > no correlation between an incoming connection to to

Re: Re-Use TCP Source Ports if the Socket is Unique?

Eric, On 6/24/21 21:14, Eric Robinson wrote: I guess I may have answered this question for myself. At least I can simulate it with ncat. Note that I have two ncat sessions open to the same remote server using the same source port, but with different source IPs. [root@testserver ~]# netstat -ant

Re: Re-Use TCP Source Ports if the Socket is Unique?

On 25.06.21 14:46, Eric Robinson wrote: > Olaf and Scott -- > > Thanks to both of you for your comments. I may have asked my question poorly, > since what you both described is the way I understand TCP to work. There is > no correlation between an incoming connection to tomcat and its outgoing

RE: Re-Use TCP Source Ports if the Socket is Unique?

Olaf and Scott -- Thanks to both of you for your comments. I may have asked my question poorly, since what you both described is the way I understand TCP to work. There is no correlation between an incoming connection to tomcat and its outgoing connection to a database backend, nor would I expe

RE: Re-Use TCP Source Ports if the Socket is Unique?

Hi Eric, > I guess the answer depends on whether the socket libraries use the tomcat > listening port as the source IP. If you have three tomcat instances listening > on three different IPs, each instance should be able to open a client > connection using the same source port, as long as each t

Re: Re-Use TCP Source Ports if the Socket is Unique?

On 25.06.21 05:19, Eric Robinson wrote: > Thanks for the feedback, Daniel. > > I guess the answer depends on whether the socket libraries use the tomcat > listening port as the source IP. If you have three tomcat instances listening > on three different IPs, each instance should be able to open