Why Increasing Buffer Credits Is Not A Cure For A Slow Drain Device


When I am working on performance problems, a frequent question I  get is why increasing buffer credits for a particular port is not a fix for a slow drain device attached to that port.  In this video, I explain the concept of congestion and illustrate why increasing the number of buffer credits is not a fix, without addressing the underlying cause of the congestion.   There are some exceptions to this rule.  The most common is when dealing with long-distance links, but that will be addressed in a future blog post (and perhaps a future video).  




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