HAST instability

Daniel Kalchev daniel at digsys.bg
Tue Jun 14 15:07:39 UTC 2011

On 14.06.11 17:56, Mikolaj Golub wrote:
> It has turned out that automatic receive buffer sizing works only for
> connections in ESTABLISHED state. And with small receive buffer the connection
> might stuck sending data only via TCP window probes -- one byte every few
> seconds (see "Scenario to make recv(MSG_WAITALL) stuck" in net@ for details).
I have tried some TCP/IP tuning to help utilize the faster network, but 
for the moment it is likely local disks limit the throughput to about 
230 MB/sec peak. The peaks now are the same as before, but now the total 
performance is better.

However, it may turn out that single TCP/IP session across 10Gbit 
network would not be able to achieve very high throughput. It may be 
beneficial to support multiple parallel TCP/IP connections between 
primary/slave in order to utilize faster networks.


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