A `StatsClient` for `expvar` is added so we can track Stats through
the `/debug/vars` endpoint. Tags are nested inside maps so that we
can see stats for db, frame & slice.
Also added a `MultiStatsClient` for chaining multiple `StatsClient`
implementations together (e.g. `expvar` and DataDog).
This commit moves the cache flush to the `Index` and only serializes
a single fragment at a time.
Also included in this commit is the `inspect` command for the
`pilsoactl` binary. This provides insight into pilosa data files.
This commit adds a `Closing` channel to the `IndexSyncer` and the
`FragmentSyncer` that is periodically checked during execution.
If the channel is closed then an in-progress sync is immediately
stopped.
This commit changes the fragment allocation algorithm in the cluster
to make use of the `DB` name. This allows each database to use a
different slice distribution.
Initially, the `frame` was going to be used for allocation, however,
this was problematic since queries can span multiple frames so it's
impossible to choose a single frame to use.
This commit refactors the anti-entropy system to fetch data from
all replicated blocks and only set/clear bits which deviate from
the consensus between all blocks.
An example of this is if 3 nodes had the following bits set for
a single bitmap:
Node A: 1 2 3
Node B: 2 4
Node C: 1 2 4
Then only bits which are set on a majority will be set. In this
case bits 1, 2, & 4 are set but 3 only exists on a single node.
The node performing the merge would then determine the following
set/clear diffs for each node:
Node A: clear(3), set(4)
Node B: set(1)
Node C: none
Once the merge is performed and all nodes receive their diff
instructions then the nodes will be in sync:
Node A: 1 2 4
Node B: 1 2 4
Node C: 1 2 4
There still exists situations where bits can be reset. If Node A
is up and Node B & C are down then Node A's bits will be reset
once B & C come back online. We should add write consistency
settings for incoming writes so that we can ensure that a quorum
is written to before returning a success. This is outside the
scope of this commit though.
This commit adds a simple benchmarking utility to the `pilosactl`
binary. It currently only supports individual `SetBit()` commands
but it's a good start towards making a generic benchmarking
framework at the integration level.
The subcommands and usage/help messages were also cleaned up to
output correctly.
This commit adds a new HTTP handler to return a list of all databases
and frames in the index:
GET /schema
This returns JSON in the following format:
{
"dbs":[
{
"name":"d0",
"frames":[
{"name":"f0"},
{"name":"f1"}
]
}
]
}
Fixes#61
This commit adds the ability to set string, integer, and boolean
values on bitmaps and profiles within Pilosa. Bitmap attributes
are automatically returned when making a `Bitmap()` call. Profile
attributes must be requested by setting `profile=true` in the
URL.
The function names have also been renamed to initial caps so that
the PQL query language can support math operations in the future.
This commit attaches the mmap-backed roaring bitmaps as storage
to the fragments. Currently snapshotting is not supported from
Pilosa so the WAL will grow indefinitely, however, it is not a
difficult change to make.
This commit refactors the pilosa codebase. It makes several major
changes:
* Removes bitmap handles
* Removes dispatch/hold/transport
* Removes etcd dependency
* Adds consistent hash ring for slice placement
* Refactors parser/lexer
* Adds strong typing to PQL AST
* Flattens package hierarchy
