Hi, I'm comparing different configurations of LRC with Reed-Solomon. Specifically I'm comparing the total data read in all OSDs during a reconstruction of a single node (I drop a single OSD and measure until the system is stable again). While most of the configurations output the desired result, a certain configuration stood out. The expectation in the following configuration is that RS would generate 40% more reads, however LRC generated 8% more.
RS configuration: k=4, m=6 LRC configuration: sudo ceph osd erasure-code-profile set myprofile \ plugin=lrc \ mapping=DD_DD_____ \ layers='[ [ "DD_DD_cccc", "" ], [ "DDc_______", "" ], [ "___DDc____", "" ], ]' \ ruleset-steps='[ [ "chooseleaf", "osd", 10 ], ]' RS will always require 4 nodes for reconstruction, however LRC would use less (4 in worst case and 2 in best). Any thoughts on this matter? Thanks, Oleg
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