Erlang node suffers high cpu -

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i use perf detect node's process

perf command: perf record -g -p 13586 sleep 10

result:

# events: 7k cpu-clock # # overhead  command       shared object                                symbol # ........  .......  ..................  .................................... #     17.02%     beam  beam                [.] copy_struct                |                --- copy_struct      12.38%     beam  beam                [.] size_object                |                --- size_object      11.85%     beam  beam                [.] db_prog_match                |                --- db_prog_match       7.78%     beam  beam                [.] db_select_hash                |                --- db_select_hash       6.90%     beam  beam                [.] process_main                |                --- process_main       4.70%     beam  beam                [.] do_minor                |                --- do_minor       4.23%     beam  beam                [.] element_2                |                --- element_2       3.30%     beam  beam                [.] sweep_one_area                |                --- sweep_one_area       1.53%     beam  beam                [.] cmp                |                --- cmp       1.39%     beam  beam                [.] copy_shallow                |                --- copy_shallow

as can see, copy_struct , size_object cost much.

are schedulers busy in copying messages?

fyi, sorted reductions desc , fetched top 10 processes on node, seems normal.

as have 6 nodes on 1 system, smp disabled. shall open on?

copy struct used whenever term in general has copies, not messages.

since db_* quite high imagine copy structs come copying data , ets tables.

regarding if should use smp or not, might make system perform better, should try , measure results system vary depending on system does.


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