This fixes various issues when initializing the head time range
under different starting conditions.
Signed-off-by: Fabian Reinartz <freinartz@google.com>
Blocks are half-open intervals [a, b), while all other intervals
(chunks, head, ...) are closed intervals [a, b].
Make that distinction explicit by defining `OverlapsClosedInterval()`
methods for blocks and chunks, and using them in place of the more
generic `intervalOverlap()` function.
This change also fixes `db.Querier()` and `db.Delete()`, which could
previously return one extraneous block at the end of the specified
interval.
Signed-off-by: Benoît Knecht <benoit.knecht@fsfe.org>
This has been a frequent source of debugging pain since errors are
potentially delayed to a much later point. They bubble up in an
unrelated execution path.
We were determining a chunk's end time once it was one quarter full to
compute it so all chunks have uniform number of samples.
This accidentally skipped the case where series started near the end of
a chunk range/block and never reached that threshold. As a result they
got persisted but were continued across the range.
This resulted in corrupted persisted data.
The postings list index may point to series that no longer
exist during garbage collection. This clarifies that this is valid
behavior.
It would be possible, though more complex, to always keep them in sync.
However, series existance means nothing in itself as the queried time
range defines whether there's actual data. Thus our definition is sane
overall as long as drift is kept small.
This commit introduces error returns in various places and is explicit
about closing persisted blocks.
{Index,Chunk,Tombstone}Readers are more consistent about their Close()
method. Whenever a reader is retrieved, the corresponding close method
must eventually be called. We use this to track pending readers against
persisted blocks.
Querier's against the DB no longer hold a read lock for their entire
lifecycle. This avoids long running queriers to starve new ones when we
have to acquire a write lock when reloading blocks.
This change fixes the variable names holding the tsdb_head_max_time and
tsdb_head_min_time metrics. It is a cosmetic change to improve the
code readability as the metric values are taken from the correct
variables.
This allows to insert IDs to postings out of order until
a trigger function is called. This avoids the insertion sort we usually
do which can be very costly since WAL entries are more out of order than
regular adds.
There is not guarantee or requirement for WAL writers to only add
series entries in increasing order of IDs. A postings list cannot look
back and thus unordered WAL entries would skip over IDs to not truncate
from the WAL.
We replace it with a simple boolean check function that does not require
order.
IDs for new series are handed out before the postings are locked. Thus
series are not indexed in order of their IDs, which could result in only
partially sorted postings list.
Iterating over those silently skipped elements as the sort invariant was
violated.
Fabian Reinartz
Fabian Reinartz
codwu
Benoît Knecht
Goutham Veeramachaneni
Matt Bostock
Simon Pasquier
Goutham Veeramachaneni
Julius Volz
Oren Shomron
Simon Pasquier