Previously, tags had a `shouldCopy` flag to indicate if those tags
referenced an underlying buffer and should be copied to allow GC.
Unfortunately, this prevented tags from being copied that were
created and referenced the mmap which caused segfaults.
This change removes the `shouldCopy` flag and replaces it with a
`forceCopy` argument in `CreateSeriesIfNotExists()`. This allows
the write path to indicate that tags must be cloned on insert.
This change delays Tag cloning until a new series is found, and will
only clone Tags acquired from `ParsePoints...` and not those referencing
the mmap-ed files (TSM) that are created on startup.
This leak seems to have been introduced in 8aa224b22d,
present in 1.1.0 and 1.1.1.
When points were parsed from HTTP payloads, their tags and fields
referred to subslices of the request body; if any tag set introduced a
new series, then those tags then were stored in the in-memory series
index objects, preventing the HTTP body from being garbage collected. If
there were no new series in the payload, then the request body would be
garbage collected as usual.
Now, we clone the tags before we store them in the index. This is an
imperfect fix because the Point still holds references to the original
tags, and the Point's field iterator also refers to the payload buffer.
However, the current write code path does not retain references to the
Point or its fields; and this change will likely be obsoleted when TSI
is introduced.
This change likely fixes#7827, #7810, #7778, and perhaps others.
I haven't been able to reproduce creating a point without any fields,
but we've seen points in the wild that have been marshalled with no
fields - that is, the length header for fields is uint32(0) and a
well-formed encoded time follows.
Attempting to unmarshal points via NewPointFromBytes returns
ErrPointMustHaveAField, so it seems better to fail earlier with the same
error, rather than allowing those points to be serialized in the first
place.
A string field w/ a trailing slash before the quote would parse incorrectly
because the quote would be seen as escaped. We have to treat \\ as an
escape sequence within strings in order to handle this.
The `partial` tag has been added to the JSON response of a series and
the result so that a client knows when more of the series or result will
be sent in a future JSON chunk.
This helps interactive clients who don't want to wait for all of the
data to know if it is done processing the current series or the current
result. Previously, the client had to guess if the next chunk would
refer to the same result or a new result and it had to match the name
and tags of the two series to know if they were the same series. Now,
the client just needs to check the `partial` field included with the
response to know if it should expect more.
Fixed `max-row-limit` so it counts rows instead of results and it
truncates the response when the `max-row-limit` is reached.
The FieldIterator is used to scan over the fields of a point, providing
information, and delaying parsing/decoding the value until it is needed.
This change uses this new type to avoid the allocation of a map for the
fields which is then thrown away as soon as the points get converted
into columns within the datastore.
+ Remove a heap alloc in (Point).HashID() and (Row).tagsHash()
(According to `-gcflags -m`).
+ Direct port from the stdlib.
+ Fuzz test for equivalence to stdlib version.
+ Save one alloc per line when writing with the bulk protocol.
Over a longer period of writes, this allocation shows up quite
a bit in profiles since the slice needs to be resized frequently.
This scans the slice to count how many lines are going to be parsed
in order to pre-allocate the slice capacity. It's slightly slower,
but creates less garbage in the long run.
The v2 UDP client will attempt to split points that exceed the
configured payload size. It will only do this for points that have a
timestamp specified.
Negative timestamps are now supported. We also now refuse two
nanoseconds that are at the edge of the minimum time window. One of the
nanoseconds we do not accept is because we need MinInt64 to be used for
some internal comparisons in the TSM engine and it was causing an
underflow when we subtracted one from the minimum time. The second is so
we can have one minimum time that signifies the default minimum that
nobody can write to (so we can implicitly rewrite the timestamp on
aggregate queries) but still use the explicit timestamp if it is given
to us by the user. We aren't able to tell the difference between if the
user provided it or if it was implicit without those values being
different.
If the default minimum time is used with an aggregate query, we rewrite
the time to be the epoch for backwards compatibility since we believe
that's more important than supporting that extra nanosecond.