- Remove some unused code
- Use `is_multiple_of()` instead of '%'
- Collapse consecuative "if let" statements
- Elided lifetime fixes
It is enough just to review the code of your team
## Problem
close LKB-753. `test_pageserver_metrics_removed_after_offload` is
unstable and it sometimes leave the metrics behind after tenant
offloading. It turns out that we triggered an image compaction before
the offload and the job was stopped after the offload request was
completed.
## Summary of changes
Wait all background tasks to finish before checking the metrics.
---------
Signed-off-by: Alex Chi Z <chi@neon.tech>
There were a few uses of these already, so collect them to the
compatibility header to avoid the repetition and scattered #ifdefs.
The definition of MyProcNumber is a little different from what was used
before, but the end result is the same. (PGPROC->pgprocno values were
just assigned sequentially to all PGPROC array members, see
InitProcGlobal(). That's a bit silly, which is why it was removed in
v17.)
## Problem
When tenants have a lot of timelines, the number of tenants that a
pageserver can comfortably handle goes down. Branching is much more
widely used in practice now than it was when this code was written, and
we generally run pageservers with a few thousand tenants (where each
tenant has many timelines), rather than the 10k-20k we might have done
historically.
This should really be something configurable, or a more direct proxy for
resource utilization (such as non-archived timeline count), but this
change should be a low effort improvement.
## Summary of changes
* Change the target shard count (MAX_SHARDS) to 2500 from 5000 when
calculating pageserver utilization (i.e. a 200% overcommit now
corresponds to 5000 shards, not 10000 shards)
Co-authored-by: John Spray <john.spray@databricks.com>
## Problem
The test for logical replication used the year-old versions of
ClickHouse and Debezium so that we may miss problems related to
up-to-date versions.
## Summary of changes
The ClickHouse version has been updated to 24.8.
The Debezium version has been updated to the latest stable one,
3.1.3Final.
Some problems with locally running the Debezium test have been fixed.
---------
Co-authored-by: Alexey Masterov <alexey.masterov@databricks.com>
Co-authored-by: Alexander Bayandin <alexander@neon.tech>
Exposes metrics for caches. LKB-2594
This exposes a high level namespace, `cache`, that all cache metrics can
be added to - this makes it easier to make library panels for the caches
as I understand it.
To calculate the current cache fill ratio, you could use the following
query:
```
(
cache_inserted_total{cache="node_info"}
- sum (cache_evicted_total{cache="node_info"}) without (cause)
)
/ cache_capacity{cache="node_info"}
```
To calculate the cache hit ratio, you could use the following query:
```
cache_request_total{cache="node_info", outcome="hit"}
/ sum (cache_request_total{cache="node_info"}) without (outcome)
```
## Problem
For certificate auth, we need to configure pg_hba and pg_ident for it to
work.
HCC needs to mount this config map to all pg compute pod.
## Summary of changes
Create `databricks_pg_hba` and `databricks_pg_ident` to configure where
the files are located on the pod. These configs are pass down to
`compute_ctl`. Compute_ctl uses these config to update `pg_hba.conf` and
`pg_ident.conf` file.
We append `include_if_exists {databricks_pg_hba}` to `pg_hba.conf` and
similarly to `pg_ident.conf`. So that it will refer to databricks config
file without much change to existing pg default config file.
---------
Co-authored-by: Jarupat Jisarojito <jarupat.jisarojito@databricks.com>
Co-authored-by: William Huang <william.huang@databricks.com>
Co-authored-by: HaoyuHuang <haoyu.huang.68@gmail.com>
Before this PR, getpage requests wouldn't hold the
`applied_gc_cutoff_lsn` guard until they were done.
Theoretical impact: if we’re not holding the `RcuReadGuard`, gc can
theoretically concurrently delete reconstruct data that we need to
reconstruct the page.
I don't think this practically occurs in production because the odds of
it happening are quite low, especially for primary read_write computes.
But RO replicas / standby_horizon relies on correct
`applied_gc_cutofff_lsn`, so, I'm fixing this as part of the work ok
replacing standby_horizon propagation mechanism with leases (LKB-88).
The change is feature-gated with a feature flag, and evaluated once when
entering `handle_pagestream` to avoid performance impact.
For observability, we add a field to the `handle_pagestream` span, and a
slow-log to the place in `gc_loop` where it waits for the in-flight
RcuReadGuard's to drain.
refs
- fixes https://databricks.atlassian.net/browse/LKB-2572
- standby_horizon leases epic:
https://databricks.atlassian.net/browse/LKB-2572
---------
Co-authored-by: Christian Schwarz <Christian Schwarz>
## Problem
Monitoring dashboards show aggregates of all proxy instances, including
terminating ones. This can skew the results or make graphs less
readable. Also, alerts must be tuned to ignore certain signals from
terminating proxies.
## Summary of changes
Add a `service_info` metric currently with one label, `state`, showing
if an instance is in state `init`, `running`, or `terminating`. The
metric can be joined with other metrics to filter the presented time
series.
## Problem
test_ps_unavailable_after_delete is flaky. All test failures I've looked
at are because of ERROR log messages in pageserver, which happen because
storage controller tries runs a reconciliations during the graceful
shutdown of the pageserver.
I wasn't able to reproduce it locally, but I think stopping PS
immediately instead of gracefully should help. If not, we might just
silence those errors.
- Closes: https://databricks.atlassian.net/browse/LKB-745
## Problem
We need the set the following Postgres GUCs to the correct value before
starting Postgres in the compute instance:
```
databricks.workspace_url
databricks.enable_databricks_identity_login
databricks.enable_sql_restrictions
```
## Summary of changes
Plumbed through `workspace_url` and other GUC settings via
`DatabricksSettings` in `ComputeSpec`. The spec is sent to the compute
instance when it starts up and the GUCs are written to `postgresql.conf`
before the postgres process is launched.
---------
Co-authored-by: Jarupat Jisarojito <jarupat.jisarojito@databricks.com>
Co-authored-by: William Huang <william.huang@databricks.com>
## Problem
Copy certificate and key from secret mount directory to `pgdata`
directory where `postgres` is the owner and we can set the key
permission to 0600.
## Summary of changes
- Added new pgparam `pg_compute_tls_settings` to specify where k8s
secret for certificate and key are mounted.
- Added a new field to `ComputeSpec` called `databricks_settings`. This
is a struct that will be used to store any other settings that needs to
be propagate to Compute but should not be persisted to `ComputeSpec` in
the database.
- Then when the compute container start up, as part of `prepare_pgdata`
function, it will copied `server.key` and `server.crt` from k8s mounted
directory to `pgdata` directory.
## How is this tested?
Add unit tests.
Manual test via KIND
Co-authored-by: Jarupat Jisarojito <jarupat.jisarojito@databricks.com>
## Problem
We saw the following in the field:
Context and observations:
* The storage controller keeps track of the latest generations and the
pageserver that issued the latest generation in the database
* When the storage controller needs to proxy a request (e.g. timeline
creation) to the pageservers, it will find use the pageserver that
issued the latest generation from the db (generation_pageserver).
* pageserver-2.cell-2 got into a bad state and wasn't able to apply
location_config (e.g. detach a shard)
What happened:
1. pageserver-2.cell-2 was a secondary for our shard since we were not
able to detach it
2. control plane asked to detach a tenant (presumably because it was
idle)
a. In response storcon clears the generation_pageserver from the db and
attempts to detach all locations
b. it tries to detach pageserver-2.cell-2 first, but fails, which fails
the entire reconciliation leaving the good attached location still there
c. return success to cplane
3. control plane asks to re-attach the tenant
a. In response storcon performs a reconciliation
b. it finds that the observed state matches the intent (remember we did
not detach the primary at step(2))
c. skips incrementing the genration and setting the
generation_pageserver column
Now any requests that need to be proxied to pageservers and rely on the
generation_pageserver db column fail because that's not set
## Summary of changes
1. We do all non-essential location config calls (setting up
secondaries,
detaches) at the end of the reconciliation. Previously, we bailed out
of the reconciliation on the first failure. With this patch we attempt
all of the RPCs.
This allows the observed state to update even if another RPC failed for
unrelated reasons.
2. If the overall reconciliation failed, we don't want to remove nodes
from the
observed state as a safe-guard. With the previous patch, we'll get a
deletion delta to process, which would be ignored. Ignoring it is not
the right thing to do since it's out of sync with the db state.
Hence, on reconciliation failures map deletion from the observed state
to the uncertain state. Future reconciliation will query the node to
refresh their observed state.
Closes LKB-204
Verify that gRPC `GetPageRequest` has been sent to the shard that owns
the pages. This avoid spurious `NotFound` errors if a compute misroutes
a request, which can appear scarier (e.g. data loss).
Touches [LKB-191](https://databricks.atlassian.net/browse/LKB-191).
