user/dev discussion of public-inbox itself
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From: Eric Wong <e@80x24.org>
To: meta@public-inbox.org
Subject: [PATCH 0/4] xcpdb: support resharding Xapian DBs
Date: Fri, 14 Jun 2019 03:03:14 +0000
Message-ID: <20190614030318.17216-1-e@80x24.org> (raw)

Defaulting the number of Xapian shards based on the number
of CPUs can be detrimental to performance given the lack of
speed in common storage systems; since NVMe speeds are not
yet common.

To help public-inbox users recover from this inefficiency while
allowing continuous email archival, we can support arbitrary
resharding to have fewer shards (or more, if doing HW upgrades).

Note: I'm also going to move the documentation towards using the
word "shard" (instead of "partition") to be consistent with
current Xapian documentation (1.4+, and "master").

Xapian 1.2 did not use the word "shard" at all, but IME from my
interactions with non-Xapian search engine folks, the word
"shard" is pretty common.

Eric Wong (4):
  v2writable: use a smaller default for Xapian partitions
  xapcmd: preserve indexlevel based on the destination
  xcpdb: use destination shard as progress prefix
  xcpdb: support resharding v2 repos

 Documentation/public-inbox-xcpdb.pod |  11 ++
 MANIFEST                             |   1 +
 lib/PublicInbox/V2Writable.pm        |  18 ++-
 lib/PublicInbox/Xapcmd.pm            | 222 +++++++++++++++++++++------
 script/public-inbox-xcpdb            |   4 +-
 t/xcpdb-reshard.t                    |  83 ++++++++++
 6 files changed, 286 insertions(+), 53 deletions(-)
 create mode 100644 t/xcpdb-reshard.t

-- 
EW


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Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-14  3:03 Eric Wong [this message]
2019-06-14  3:03 ` [PATCH 1/4] v2writable: use a smaller default for Xapian partitions Eric Wong
2019-06-14  3:03 ` [PATCH 2/4] xapcmd: preserve indexlevel based on the destination Eric Wong
2019-06-14  3:03 ` [PATCH 3/4] xcpdb: use destination shard as progress prefix Eric Wong
2019-06-14  3:03 ` [PATCH 4/4] xcpdb: support resharding v2 repos Eric Wong

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