Search Tiers

The Xapian search engine supports searching from multiple databases at once, creating a tiered database structure. To use Xapian, these tiers must be defined in imapd.conf(5) with the defaultsearchtier and searchpartition-name options.

Default Search Tier Name

Specify the name of the default search tier using the defaultsearchtier setting.

Search Tier Partition Location

Each search tier to be used requires a partition location be specified via a searchpartition-name setting, wherein "name" is replaced with the name of the mail spool for which this search partition is to be used, and prepended by the name of the tier with which it is associated:

{tier}searchpartition-{spool}

Again, building on our examples from Spool Directories, here we have three spool partitions defined, so we need three search partitions for each tier. In this example, with just a single tier, we will be adding three search partitions.

• Sample:

  defaultpartition: main
  partition-main: /var/spool/cyrus
  partition-am: /var/spool/cyrus-am
  partition-nz: /var/spool/cyrus-nz
  partition-shared: /var/spool/cyrus-shared
  metapartition_files: header index cache expunge squat annotations
  metapartition-main: /var/spool/cyrusmeta/main
  metapartition-am: /var/spool/cyrusmeta/am
  metapartition-nz: /var/spool/cyrusmeta/nz
  metapartition-shared: /var/spool/cyrusmeta/shared
  search_engine: xapian
  search_index_headers: no
  search_batchsize: 8192
  defaultsearchtier: temp
  tempsearchpartition-main: /var/spool/search/main
  tempsearchpartition-am: /var/spool/search/am
  tempsearchpartition-nz: /var/spool/search/nz
  tempsearchpartition-shared: /var/spool/search/shared