Hi! On Fri, Nov 04, 2016 at 06:33:29PM +0530, Jagbir wrote: > Hi, > > I've upgraded haproxy from 1.5.18 to 1.6.9 and perplexed to see huge drop > in memory utilisation (1.5.18 almost consuming 4x more RAM). Would like to > understand whether it's due to certain improvements/bug fixes (I've glanced > through change log but didn't notice anything significant in this context) > or due to something which might be deteriorating my user's experience here > and command deeper look?
It's because 1.6 allocates buffers only when they have to store data, while 1.5 keeps buffers allocated for a session during its whole life time. It was an important change in 1.6 allowing much higher connection counts to be reached with the same amount of RAM. In fact, I think you're the first one to report this and given your number of connections, it starts to matter a lot in your case. For most users running an order of magnitude lower, the gain is minimal. Another nice benefit of this is that you can easily increase the buffer size if you need without automatically increasing the memory usage by a proportional factor. Cheers, Willy
