During runtime eblob collects and saves to database's
.stat file various internal statistics. They are useful for automation, monitoring, graphing scripts.
GLOBAL: datasort_status: 0 read_copy_updates: 3049 prepare_reused: 147 memory_index_tree: 5520 SUMMARY: records_total: 52 records_removed: 34 records_corrupted: 0 base_size: 16787 memory_bloom_filter: 640 memory_index_blocks: 160 BASE: test-blob-0.0 records_total: 20 records_removed: 20 records_corrupted: 0 base_size: 6799 memory_bloom_filter: 640 memory_index_blocks: 160 BASE: test-blob-0.1 records_total: 32 records_removed: 14 records_corrupted: 0 base_size: 9988 memory_bloom_filter: 0 memory_index_blocks: 0
Stats are divided into three parts:
GLOBAL– stats that do not belong to specific base. Most of run-time stats are kept here, like:
datasort_status– current data-sort state, where
1means data-sort is in progress,
0- it's not, and
<0means previous data-sort ended up with an error;
read_copy_updates– number of writes that are not done in-place, but resulted in read-copy-update cycle.
prepare_reused– number of times
prepare()became a no-op because there was enough space in previous entry and that space can be “re-used” by rewriting entry in-place.
memory_index_tree– number of bytes occupied by in-memory key-tree hash. It represents all entries that do not currently have sorted-ondisk-index. Sorted ondisk index can be created either by re-initialization of eblob (e.g. elliptics restart) or by running data-sort. Memory occupied by in-memory key tree be reduced by decreasing maximum number of entries in each base(
records_in_blob), maximum size of base(
blob_size) or by running data-sort.
SUMMARY– sum() across all
BASE– stats that are specific to given base:
records_total– total number of records in given base.
records_removed– number of records marked as
records_corrupted– number of corrupted entries in given base.
base_size– disk size of base + it's sorted index.
memory_bloom_filter– number of bytes of memory occupied by bloom filter. Can be reduced by decreasing number of bloom bits per index block (
memory_index_blocks– can be reduced by increasing number of entries in index block (