Network becomes slow and return fast only after restart network

Linux and Unix-Like Red Hat
1

Hi,
I have 2 machines in production environment:

  1. redhat machine for application
  2. DB machine (oracle)

The application doing a lot of small read&writes from and to the DB machine.

The problem is that after some few hours the network from the application to the DB becomes very slow and it returns to the normal only after:

service network restart

Before:

64 bytes from hostname.domain (xxx.xxx.xxx.xxx): icmp_seq=1 ttl=63 time=7.81 ms
64 bytes from hostname.domain (xxx.xxx.xxx.xxx): icmp_seq=2 ttl=63 time=5.88 ms
64 bytes from hostname.domain (xxx.xxx.xxx.xxx): icmp_seq=3 ttl=63 time=7.81 ms

After restart network:

64 bytes from hostname.domain (xxx.xxx.xxx.xxx): icmp_seq=84 ttl=63 time=0.135 ms
64 bytes from hostname.domain (xxx.xxx.xxx.xxx): icmp_seq=85 ttl=63 time=0.171 ms
64 bytes from hostname.domain (xxx.xxx.xxx.xxx): icmp_seq=86 ttl=63 time=0.153 ms

What can it be?
How can i solve this strange behavior?

Thanks.

2

UP (?)

3

maybe upload choking :confused:

4

There may be repeated rogue queries that are trying to return vast amounts of data. If the user is disconnected/timed out/gets bored, they may well re-issue. I would consider reading the application logs to check that the queries are indeed going to return suitable data volumes.

This was learned from prolonged painful experience eventually leading to better validation and sanity checking on the application server before the query was executed.

Robin

5

You really have not given us anything to work with other than "my network slows down over time"

Have you installed the sysstat package and configured sar? Look at the output of "sar -n DEV". Anything interesting? Have you checked if the number of open sockets is increasing over time?