Comment 2 for bug 1358583
Revision history for this message
| Andrew Laski (alaski) wrote Re: List instances by IP results in DoS of nova-network | #2 |
© 2004
Canonical Ltd.
•
Terms of use
•
Data privacy
•
Contact Launchpad Support
•
Blog
•
Careers
•
System status
•
bbfa235
(Get the code!)
As the comment in the linked code indicates, that method is not going to work well for large amounts of data. The worst bottleneck is probably going to be the length of time it takes to complete the sql query and retrieve the data. Unfortunately the mysql library used by Nova blocks when it makes a call, so everything stops in that process for the time it takes to complete. But there should be one nova-network process per CPU of the machine it's running on, so even when one is blocked work can continue on the others. And though the processing after retrieving the data will be CPU intensive, it should not prevent work in other processes or greenthreads from continuing.
But, multiple queries could tie up all of the nova-network processes and lead to a degradation of services. In short, I think there is potential for a DoS here.