Description of problem: Documentation talking about/explaining block sizes in relation to the iGW, to give a better "picture" of the data flow between iGW Client and RBD Image. An example could be how changing the ESXi setting "Disk.DiskMaxIOSize"[1] from it's default value of 32767, would affect the iGW performance. Version-Release number of selected component (if applicable): Supported versions of ESXi. [1] https://kb.vmware.com/s/article/1003469
Loosely affiliated, the following parameters could be added alongside Disk.DiskMaxIOSize: ISCSI.MaxIoSizeKB Misc.APDTimeout And an explanation on what scenarios can trigger the igw to reject requests, such as too slow IO, due to deep-scrub on a NL deviceclass, sharing LUN export with a much faster class. (happens on 3.x, not sure about 4.x)