Using crushtool reclassify to insert device class into existing crush map
Hi, We are trying to introduce SSD/NvME OSD’s and to prevent data moving from current (hdd based) OSD’s while also having erasure coded pools we could not just simply change the erasure coding profile or create a new one and just apply it to the pool. Reading this list and other posts on forums it was suggested to use the crushtool reclassify to insert device classes into the current crush rules and load that crush map manually. Not having edited the crush map in this or any other fashion earlier I would appreciate very much if I someone could verify if I have done the reclassify correctly. Thank you, [root@cephyr-mon1 crushtest]# crushtool -i crush_comp.c --reclassify --reclassify-root default hdd -o crush_comp_corr.c classify_root default (-1) as hdd renumbering bucket -1 -> -29 renumbering bucket -27 -> -30 renumbering bucket -25 -> -31 renumbering bucket -23 -> -32 renumbering bucket -21 -> -33 renumbering bucket -19 -> -34 renumbering bucket -17 -> -35 renumbering bucket -15 -> -36 renumbering bucket -13 -> -37 renumbering bucket -11 -> -38 renumbering bucket -9 -> -39 renumbering bucket -7 -> -40 renumbering bucket -5 -> -41 renumbering bucket -3 -> -42 [root@cephyr-mon1 crushtest]# crushtool -i crush_comp.c --compare crush_comp_corr.c rule 0 had 0/10240 mismatched mappings (0) rule 6 had 0/10240 mismatched mappings (0) rule 7 had 0/4096 mismatched mappings (0) rule 8 had 0/4096 mismatched mappings (0) rule 9 had 0/4096 mismatched mappings (0) rule 10 had 0/4096 mismatched mappings (0) rule 11 had 0/4096 mismatched mappings (0) rule 12 had 0/4096 mismatched mappings (0) rule 13 had 0/4096 mismatched mappings (0) maps appear equivalent Regards, Mathias Lindberg Tel: +46 (0)31 7723059 Mob: +46 (0)723 526107 Mathias Lindberg mathlin@chalmers.se
Hi, disclaimer: I haven't used the reclassify function myself yet. But the output from crushtool looks correct to me and seems to match the description in the docs. Maybe someone else with more experience sees something odd but I think this would work as expected. Regards, Eugen Zitat von Mathias Lindberg <mathlin@chalmers.se>:
Hi,
We are trying to introduce SSD/NvME OSD’s and to prevent data moving from current (hdd based) OSD’s while also having erasure coded pools we could not just simply change the erasure coding profile or create a new one and just apply it to the pool.
Reading this list and other posts on forums it was suggested to use the crushtool reclassify to insert device classes into the current crush rules and load that crush map manually. Not having edited the crush map in this or any other fashion earlier I would appreciate very much if I someone could verify if I have done the reclassify correctly. Thank you,
[root@cephyr-mon1 crushtest]# crushtool -i crush_comp.c --reclassify --reclassify-root default hdd -o crush_comp_corr.c classify_root default (-1) as hdd renumbering bucket -1 -> -29 renumbering bucket -27 -> -30 renumbering bucket -25 -> -31 renumbering bucket -23 -> -32 renumbering bucket -21 -> -33 renumbering bucket -19 -> -34 renumbering bucket -17 -> -35 renumbering bucket -15 -> -36 renumbering bucket -13 -> -37 renumbering bucket -11 -> -38 renumbering bucket -9 -> -39 renumbering bucket -7 -> -40 renumbering bucket -5 -> -41 renumbering bucket -3 -> -42
[root@cephyr-mon1 crushtest]# crushtool -i crush_comp.c --compare crush_comp_corr.c rule 0 had 0/10240 mismatched mappings (0) rule 6 had 0/10240 mismatched mappings (0) rule 7 had 0/4096 mismatched mappings (0) rule 8 had 0/4096 mismatched mappings (0) rule 9 had 0/4096 mismatched mappings (0) rule 10 had 0/4096 mismatched mappings (0) rule 11 had 0/4096 mismatched mappings (0) rule 12 had 0/4096 mismatched mappings (0) rule 13 had 0/4096 mismatched mappings (0) maps appear equivalent
Regards, Mathias Lindberg
Tel: +46 (0)31 7723059 Mob: +46 (0)723 526107 Mathias Lindberg mathlin@chalmers.se
participants (2)
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Eugen Block
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Mathias Lindberg