Receiving other thread HGETALL request result on high memory pressure and multiple threads

[jcaspes]

Hello,

While testing the StackExchange.Redis library (on HGETALL api) under high memory pressure to induce frequent OutOfMemory exceptions, I encountered cases where received data is valid but not expected and appears to be the query result from an other thread.

Tested with this program: https://github.com/jcaspes/StackExchange.Redis/tree/MemoryTester/toys/MemoryTester

In this program, each thread only performs infinite HGETALL operations on a key with its thread ID, so it should only retrieve data that it has written itself.

Here a sample output; we can see that thread 218 (Th218hT) retrieved valid data that was queried by thread 58 (Th58hT)

218 : Error in key, expected:Th218hT, actual:Th58hT, value is a valid but from an other query: True