Eventstore 4.0.3 I/O performance

Hi all,

Has anyone recently deployed Eventstore 4.0.3 on Ubuntu 16.0.4, (physical servers) and seen degradation of I/O performance from the storagewriter thread. Interestingly the stats gathered from other Eventstore instances deployed on Windows platform a better picture.
Can anyone shed any light on how Eventstore uses buffer/Page caches on the Linux platform ?