The problem is that accidental timeout errors can make us to ignore
other nodes for some time. The primary purpose of the whole ignore
mechanism is not to degrade in case of failover. For this case,
closing connection and limiting the amount of dials is enough.
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
In case we have many small objects in the write-cache, `indices` should
not be reused between iterations.
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
Missing `ReportError` method did not allow casing multi-client interface to
`errorReporter` interface and dropping broken connections.
`replicationClient` embeds that interface, and it is widely used across
node's code. Embedded interface does not allow casting its parent structure
to `errorReporter` and breaks multi client error reporting logic.
Multi-client scheme is extremely hard to maintain, it makes unpredictable
casts and does not allow tracking code flow, so it will be refactored in the
future anyway.
Signed-off-by: Pavel Karpy <p.karpy@yadro.com>
Previously, node could get an "infinite" small object: it could be expired
and thus could not be flushed (update its storage ID) to metabase => could
not be marked as flushed => node never removes such object and repeat all
the cycle one more time. If object exists and is not marked with GC (meta
returns `ErrObjectIsExpired`, not `ObjectNotFound` and not
`ObjectAlreadyRemoved`), its ID is safe to update _in the same_ bbolt
transaction.
Signed-off-by: Pavel Karpy <p.karpy@yadro.com>
LRU `Peek`/`Contains` take LRU mutex _inside_ of a `View` transaction.
`View` transaction itself takes `mmapLock` [1], which is lifted after tx
finishes (in `tx.Commit()` -> `tx.close()` -> `tx.db.removeTx`)
When we evict items from LRU cache mutex order is different:
first we take LRU mutex and then execute `Batch` which _does_ take
`mmapLock` in case we need to remap. Thus the deadlock.
[1] 8f4a7e1f92/db.go (L708)
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
To achieve high performance we must choose proper values for both
batch size and delay. For user operations we want to set low delay.
However it would prevent tree synchronization operations to form big
enough batches. For these operations, batching gives the most benefit
not only in terms of on-CPU execution cost, but also by speeding up
transaction persist (`fsync`).
In this commit we try merging batches that are already
_triggered_, but not yet _started to execute_. This way we can still
query batches for execution after the provided delay while also allowing
multiple formed batches to execute faster.
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
"Object is expired" means that object is presented in `meta` but it is not
`ObjectNotFound` error. Previous implementation made `shard` search for an
object without `meta` which was an error.
Signed-off-by: Pavel Karpy <p.karpy@yadro.com>
```
name old time/op new time/op delta
_addressFromString-8 1.25µs ±30% 1.02µs ± 6% -18.49% (p=0.000 n=9+9)
name old alloc/op new alloc/op delta
_addressFromString-8 352B ± 0% 256B ± 0% -27.27% (p=0.000 n=9+10)
name old allocs/op new allocs/op delta
_addressFromString-8 6.00 ± 0% 4.00 ± 0% -33.33% (p=0.000
n=10+10)
```
Also, assure compiler that `s` doesn't escape:
Before this commit:
```
./fstree.go:74:24: leaking param: s
./fstree.go:90:6: moved to heap: addr
```
After this commit:
```
./fstree.go:74:24: s does not escape
```
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
Currently we track based on `PayloadSize`, because it is already stored
in the metabase and it is easier to calculate without slowing down the
whole system.
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
Signed-off-by: Pavel Karpy <p.karpy@yadro.com>
Currently the only way to tell whether `evacuate/set-mode` is finished
is to set a very big timeout and _hope_ that the operation will finish.
In this commit we add INFO logs for such operations which should
simplify the life of an administrator.
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
Currently, under high load clients are blocked on channel send
and the number of goroutines can increase indefinitely.
In this commit we drop replication messages if send/recv queue is full
and rely on a background synchronization.
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
1. Reduce allocations inside transactions.
2. Do not encode container ID to string: it allocates a lot and takes more
space.
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
Under high load we are limited by the _amount_ of keys we need to update
in a single transaction. In this commit we try storing all state
with a single key.
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
