Slow Drains impact on your SAN

See this recent blog post by Erik Smith (@provandal) regarding the impact of Slow Drain conditions on your SAN.

     "If you work with Fibre Channel on a regular basis and have come to depend on its excellent performance attributes, you might be surprised to learn that many of the cases handled by our SAN team in Customer Support are related to performance problems.  Typically, as we dig into these cases, we discover the majority of them are not actually caused by the FC switches themselves, but rather by end devices that are not performing as expected and are causing fabric wide congestion.  These misbehaving end devices are referred to as “slow drains” and they represent a well-known class of problem that is inherent to all lossless transports including FC, DCB Ethernet (e.g., FCoE, RoCE) and even wastewater drain systems (e.g., “Plumbing”)."

     http://brasstacksblog.typepad.com/brass-tacks/2016/02/slow-drains-are-impacting-your-san.html