Status Variables

SHOW GLOBAL STATUS LIKE 'tidesdb%';

or from performance_schema, which is where this server keeps the status tables:

SELECT VARIABLE_NAME, VARIABLE_VALUE FROM performance_schema.global_status
WHERE VARIABLE_NAME LIKE 'tidesdb%';

These are the machine-readable counters for a monitoring agent such as a Prometheus exporter or PMM. Monitoring explains which of them matter and what healthy looks like. They are refreshed on demand behind a short coalescing window, so reading many of them in one statement costs a single stats pass.

Identity

Variable	Description
`tidesdb_version`	TideSQL plugin version string, for example `2.0.0`
`tidesdb_version_hex`	Plugin version as an integer, major-minor-patch a byte each, for example `131072` for `0x020000`
`tidesdb_library_version`	Linked TidesDB library version string

Sequence and transactions

Variable	Description
`tidesdb_column_families`	Number of active column families
`tidesdb_global_sequence`	Global MVCC sequence number
`tidesdb_min_snapshot_sequence`	Oldest pinned snapshot, the floor compaction cannot reclaim past
`tidesdb_active_transactions`	Transactions currently joined to the MVCC registry
`tidesdb_txn_memory_bytes`	Memory held by in-flight transactions in bytes

Memory and storage

Variable	Description
`tidesdb_memtable_bytes`	Bytes in the active memtable
`tidesdb_total_sstables`	Total SSTable count across all column families
`tidesdb_open_sstables`	Open SSTable file handles
`tidesdb_data_size_bytes`	Total on-disk data size in bytes
`tidesdb_immutable_memtables`	Sealed memtables waiting to be flushed
`tidesdb_flush_pending`	Flushes pending (the immutable memtable queue depth)
`tidesdb_compaction_queue`	Compaction jobs queued for the worker pool
`tidesdb_memtable_is_flushing`	1 while an immutable is queued or flushing
`tidesdb_wal_generation`	Current write-ahead-log generation counter

Value log

Variable	Description
`tidesdb_vlog_file_size`	On-disk size of the value log in bytes
`tidesdb_vlog_value_count`	Values the value log currently indexes
`tidesdb_vlog_used_bytes`	Uncompressed length those values represent
`tidesdb_vlog_bytes_written`	Lifetime bytes appended to the value log, output the flush and compaction counters do not see once values separate

Encoding

Aggregate codec-chain totals summed across every chain, so logical divided by stored is the realized compression ratio for each log. The per-chain codec breakdown prints in SHOW ENGINE TIDESDB STATUS.

Variable	Description
`tidesdb_klog_logical_bytes`	Key-log bytes before encoding, summed across chains
`tidesdb_klog_stored_bytes`	Key-log bytes after encoding as stored on disk
`tidesdb_vlog_encoded_logical_bytes`	Value-log bytes before encoding, summed across chains
`tidesdb_vlog_encoded_stored_bytes`	Value-log bytes after encoding as stored on disk

Device IO

Write accounting from the library’s file-descriptor manager, which meters the SSTable and WAL devices. The value log keeps its own byte accounting in the value-log counters above. These counters are writes only, there is no read-side or syscall figure.

Variable	Description
`tidesdb_io_sstable_write_ops`	SSTable device writes issued since open
`tidesdb_io_sstable_write_bytes`	Bytes written to the SSTable device since open
`tidesdb_io_wal_write_ops`	WAL device writes issued since open
`tidesdb_io_wal_write_bytes`	Bytes written to the WAL device since open

Write amplification

Variable	Description
`tidesdb_user_bytes_written`	Logical committed bytes, the write-amplification denominator
`tidesdb_flush_bytes_written`	Bytes written to SSTables by flush jobs
`tidesdb_compaction_bytes_written`	Bytes written by compaction jobs
`tidesdb_compaction_bytes_read`	Bytes compaction read as input
`tidesdb_flush_count`	Flushes completed across all column families
`tidesdb_compaction_count`	Compactions completed across all column families

Write stalls

Variable	Description
`tidesdb_writes_throttled`	Commits the L0 admission policy made dwell before admitting
`tidesdb_writes_blocked`	Commits it made wait for the flush queue to drain
`tidesdb_write_stall_us`	Total microseconds commits spent held in admission
`tidesdb_write_stall_ceiling_hits`	Commits admitted only because the wait ceiling expired. Any sustained increase means flush is not keeping up with ingest

The aggregate counters above sum admission stall time. These per-reason counts split how often a commit stalled by cause, so backpressure can be attributed. The per-reason stall time prints in SHOW ENGINE TIDESDB STATUS.

Variable	Description
`tidesdb_stall_wal_append`	Commits that stalled appending to the write-ahead log
`tidesdb_stall_rotate_lock`	Commits that stalled taking the memtable rotation lock
`tidesdb_stall_rotate_work`	Commits that stalled while a memtable rotation was in progress
`tidesdb_stall_admission`	Commits that stalled on the unflushed-backlog admission gate
`tidesdb_stall_manifest_commit`	Commits that stalled waiting for a manifest commit

Block cache

Variable	Description
`tidesdb_cache_entries`	Cached entry count
`tidesdb_cache_bytes`	Bytes used by the block cache
`tidesdb_cache_hits`	Cache hits since open
`tidesdb_cache_misses`	Cache misses since open
`tidesdb_cache_hit_rate`	Hit rate as a percentage
`tidesdb_cache_partitions`	Number of cache shards

Tombstones

Variable	Description
`tidesdb_total_tombstones`	Total tombstones summed across every column family
`tidesdb_tombstone_ratio`	Database-wide tombstone count divided by entry count, 0.0 to 1.0
`tidesdb_max_sst_tombstone_density`	Worst single-SSTable tombstone density observed
`tidesdb_max_sst_tombstone_density_level`	1-based LSM level where the worst SSTable sits