1What: /sys/bus/nd/devices/regionX/nfit/ecc_unit_size 2Date: Aug, 2017 3KernelVersion: v4.14 (Removed v4.18) 4Contact: nvdimm@lists.linux.dev 5Description: 6 (RO) Size of a write request to a DIMM that will not incur a 7 read-modify-write cycle at the memory controller. 8 9 When the nfit driver initializes it runs an ARS (Address Range 10 Scrub) operation across every pmem range. Part of that process 11 involves determining the ARS capabilities of a given address 12 range. One of the capabilities that is reported is the 'Clear 13 Uncorrectable Error Range Length Unit Size' (see: ACPI 6.2 14 section 9.20.7.4 Function Index 1 - Query ARS Capabilities). 15 This property indicates the boundary at which the NVDIMM may 16 need to perform read-modify-write cycles to maintain ECC (Error 17 Correcting Code) blocks. 18