Advanced Configuration

Two configuration settings trade latency or memory for throughput.

Batching NOTIFY

dns.notify.batch_ms decides what happens on the write path once a change is committed.

0 (the default)

Every change sends its own NOTIFY before the write is answered. Lowest latency to visibility.

a window in milliseconds

The write is answered at commit; changes to the same zone inside the window collapse into one NOTIFY, sent from a queue. Worth it when many records change at once.

Sizing the transfer cache

dns.transfer_cache.max_records limits the record count. Approximate memory costs depend on the record contents:

Record	Cost
A with a short name	130 bytes
TXT with a 255-byte value	375 bytes
TXT carrying a DKIM key	860 bytes

The default of 500,000 records is about 64 MiB of plain address records, more where large TXT values or a signed zone's derived records dominate. Watch bindizr_zone_cache_records against the limit and bindizr_zone_cache_evictions_total: evictions rising beside a low hit ratio in bindizr_zone_cache_lookups_total mean the working set does not fit.