General Rust Write trait semantics (as well as its async brother) is that write
definitely happens only after Write::flush(). This wasn't needed in sync where
rust write calls the syscall directly, but is required in async.
Also fix setting initial end_pos in walsender, sometimes it was from the future.
fixes https://github.com/neondatabase/neon/issues/4518
## Problem
Compute is not always able to reconnect to pages server.
First of all it caused by long time of restart of pageserver.
So number of attempts is increased from 5 (hardcoded) to 60 (GUC).
Also we do not perform flush after each command to increase performance
(it is especially critical for prefetch).
Unfortunately such pending flush makes it not possible to transparently
reconnect to restarted pageserver.
What we can do is to try to minimzie such probabilty.
Most likely broken connection will be detected in first sens command
after some idle period.
This is why max_flush_delay parameter is added which force flush to be
performed after first request after some idle period.
See #4497
## Summary of changes
Add neon.max_reconnect_attempts and neon.max_glush_delay GUCs which
contol when flush has to be done
and when it is possible to try to reconnect to page server
## Checklist before requesting a review
- [ ] I have performed a self-review of my code.
- [ ] If it is a core feature, I have added thorough tests.
- [ ] Do we need to implement analytics? if so did you add the relevant
metrics to the dashboard?
- [ ] If this PR requires public announcement, mark it with
/release-notes label and add several sentences in this section.
## Checklist before merging
- [ ] Do not forget to reformat commit message to not include the above
checklist
## Problem
- Running the command according to docker.md gives warning and error.
- Warning `permissions should be u=rw (0600) or less` is output when
executing `psql -h localhost -p 55433 -U cloud_admin`.
- `FATAL: password authentication failed for user "root”` is output in
compute logs.
## Summary of changes
- Add `$ chmod 600 ~/.pgpass` in docker.md to avoid warning.
- Add username (cloud_admin) to pg_isready command in docker-compose.yml
to avoid error.
---------
Co-authored-by: Tomoka Hayashi <tomoka.hayashi@ntt.com>
```
CREATE EXTENSION embedding;
CREATE TABLE t (val real[]);
INSERT INTO t (val) VALUES ('{0,0,0}'), ('{1,2,3}'), ('{1,1,1}'), (NULL);
CREATE INDEX ON t USING hnsw (val) WITH (maxelements = 10, dims=3, m=3);
INSERT INTO t (val) VALUES (array[1,2,4]);
SELECT * FROM t ORDER BY val <-> array[3,3,3];
val
---------
{1,2,3}
{1,2,4}
{1,1,1}
{0,0,0}
(5 rows)
```
Does three things:
* add a `Display` impl for `LayerFileName` equal to the `short_id`
* based on that, replace the `Layer::short_id` function by a requirement
for a `Display` impl
* use that `Display` impl in the places where the `short_id` and `file_name()` functions were used instead
Fixes#4145
Looking at logs from staging and prod, I found there are a bunch of log
lines without tenant / timeline context.
Manully walk through all task_mgr::spawn lines and fix that using the
least amount of work required.
While doing it, remove some redundant `shutting down` messages.
refs https://github.com/neondatabase/neon/issues/4222
After announcing `hnsw`, there is a hypothesis that the community will
start comparing it with `pgvector` by themselves. Therefore, let's have
an actual version of `pgvector` in Neon.
Cache up to 20 connections per endpoint. Once all pooled connections
are used current implementation can open an extra connection, so the
maximum number of simultaneous connections is not enforced.
There are more things to do here, especially with background clean-up
of closed connections, and checks for transaction state. But current
implementation allows to check for smaller coonection latencies that
this cache should bring.
## Problem
HNSW index is created in memory.
Try to prevent OOM by checking of available RAM.
## Summary of changes
## Checklist before requesting a review
- [ ] I have performed a self-review of my code.
- [ ] If it is a core feature, I have added thorough tests.
- [ ] Do we need to implement analytics? if so did you add the relevant
metrics to the dashboard?
- [ ] If this PR requires public announcement, mark it with
/release-notes label and add several sentences in this section.
## Checklist before merging
- [ ] Do not forget to reformat commit message to not include the above
checklist
---------
Co-authored-by: Konstantin Knizhnik <knizhnik@neon.tech>
