While setting up some tests, I noticed that we didn't support keycloak.
They make use of encryption JWKs as well as signature ones. Our current
jwks crate does not support parsing encryption keys which caused the
entire jwk set to fail to parse. Switching to lazy parsing fixes this.
Also while setting up tests, I couldn't use localhost jwks server as we
require HTTPS and we were using webpki so it was impossible to add a
custom CA. Enabling native roots addresses this possibility.
I saw some of our current e2e tests against our custom JWKS in s3 were
taking a while to fetch. I've added a timeout + retries to address this.
## Problem
We don't have any benchmarks for Safekeeper WAL ingestion.
## Summary of changes
Add some basic benchmarks for WAL ingestion, specifically for
`SafeKeeper::process_msg()` (single append) and `WalAcceptor` (pipelined
batch ingestion). Also add some baseline file write benchmarks.
The PROXY Protocol V2 offers a "command" concept. It can be of two
different values. "Local" and "Proxy". The spec suggests that "Local" be
used for health-checks. We can thus use this to silence logging for such
health checks such as those from NLB.
This additionally refactors the flow to be a bit more type-safe, self
documenting and using zerocopy deser.
AWS/azure private link shares extra information in the "TLV" values of
the proxy protocol v2 header. This code doesn't action on it, but it
parses it as appropriate.
It seems the ecosystem is not so keen on moving to aws-lc-rs as it's
build setup is more complicated than ring (requiring cmake).
Eventually I expect the ecosystem should pivot to
https://github.com/ctz/graviola/tree/main/rustls-graviola as it
stabilises (it has a very simply build step and license), but for now
let's try not have a headache of juggling two crypto libs.
I also noticed that tonic will just fail with tls without a default
provider, so I added some defensive code for that.
## Problem
We wish to have high level WAL decoding logic in `wal_decoder::decoder`
module.
## Summary of Changes
For this we need the `Value` and `NeonWalRecord` types accessible there, so:
1. Move `Value` and `NeonWalRecord` to `pageserver::value` and
`pageserver::record` respectively.
2. Get rid of `pageserver::repository` (follow up from (1))
3. Move PG specific WAL record types to `postgres_ffi::walrecord`. In
theory they could live in `wal_decoder`, but it would create a circular
dependency between `wal_decoder` and `postgres_ffi`. Long term it makes
sense for those types to be PG version specific, so that will work out nicely.
4. Move higher level WAL record types (to be ingested by pageserver)
into `wal_decoder::models`
Related: https://github.com/neondatabase/neon/issues/9335
Epic: https://github.com/neondatabase/neon/issues/9329
In complement to
https://github.com/neondatabase/tokio-epoll-uring/pull/56.
## Problem
We want to make tokio-epoll-uring slots waiters queue depth observable
via Prometheus.
## Summary of changes
- Add `pageserver_tokio_epoll_uring_slots_submission_queue_depth`
metrics as a `Histogram`.
- Each thread-local tokio-epoll-uring system is given a `LocalHistogram`
to observe the metrics.
- Keep a list of `Arc<ThreadLocalMetrics>` used on-demand to flush data
to the shared histogram.
- Extend `Collector::collect` to report
`pageserver_tokio_epoll_uring_slots_submission_queue_depth`.
Signed-off-by: Yuchen Liang <yuchen@neon.tech>
Co-authored-by: Christian Schwarz <christian@neon.tech>
The forever ongoing effort of juggling multiple versions of rustls :3
now with new crypto library aws-lc.
Because of dependencies, it is currently impossible to not have both
ring and aws-lc in the dep tree, therefore our only options are not
updating rustls or having both crypto backends enabled...
According to benchmarks run by the rustls maintainer, aws-lc is faster
than ring in some cases too <https://jbp.io/graviola/>, so it's not
without its upsides,
part of https://github.com/neondatabase/neon/issues/9255
## Summary of changes
Upgrade remote_storage crate to use hyper1. Hyper0 is used when
providing the streaming HTTP body to the s3 SDK, and it is refactored to
use hyper1.
Signed-off-by: Alex Chi Z <chi@neon.tech>
Update hyper and tonic again in the storage broker, this time with a fix
for the issue that made us revert the update last time.
The first commit is a revert of #9268, the second a fix for the issue.
fixes#9231.
1. Adds local-proxy to compute image and vm spec
2. Updates local-proxy config processing, writing PID to a file eagerly
3. Updates compute-ctl to understand local proxy compute spec and to
send SIGHUP to local-proxy over that pid.
closes https://github.com/neondatabase/cloud/issues/16867
## Problem
The S3 tests couldn't use SSO authentication for local tests against S3.
## Summary of changes
Enable the `sso` feature of `aws-config`. Also run `cargo hakari
generate` which made some updates to `workspace_hack`.
Because:
- it's nice to be up-to-date,
- we already had axum 0.7 in our dependency tree, so this avoids having
to compile two versions, and
- removes one of the remaining dpendencies to hyper version 0
Also bumps the 'tokio-tungstenite' dependency, to avoid having two
versions in the dependency tree.
Fixes#9231 .
Upgrade hyper to 1.4.0 and use hyper 1.4 instead of 0.14 in the storage
broker, together with tonic 0.12. The two upgrades go hand in hand.
Thanks to the broker being independent from other components, we can
upgrade its hyper version without touching the other components, which
makes things easier.
* tracing-utils now returns a `Layer` impl. Removes the need for crates
to
import OTel crates.
* Drop the /v1/traces URI check. Verified that the code does the right
thing.
* Leave a TODO to hook in an error handler for OTel to log errors to
when it
assumes the regular pipeline cannot be used/is broken.
Part of #7497, closes#8817.
## Problem
See #8817.
## Summary of changes
**compute_ctl**
- Renew lsn lease as soon as `/configure` updates pageserver_connstr,
use `state_changed` Condvar for synchronization.
**pageserver**
As mentioned in
https://github.com/neondatabase/neon/issues/8817#issuecomment-2315768076,
we still want some permanent error reported if a lease cannot be
granted. By considering attachment mode and the added
`lsn_lease_deadline` when processing lease requests, we can also bound
the case of bad requests to a very short period after migration/restart.
- Refactor https://github.com/neondatabase/neon/pull/9024 and move
`lsn_lease_deadline` to `AttachedTenantConf` so timeline can easily
access it.
- Have separate HTTP `init_lsn_lease` and libpq `renew_lsn_lease` API.
- Always do LSN verification for the initial HTTP lease request.
- LSN verification for the renewal is **still done** when tenants are
not in `AttachedSingle` and we have pass the `lsn_lease_deadline`, which
give plenty of time for compute to renew the lease.
**neon_local**
- add and call `timeline_init_lsn_lease` mgmt_api at static endpoint
start. The initial lsn lease http request is sent when we run `cargo
neon endpoint start <static endpoint>`.
## Testing
- Extend `test_readonly_node_gc` to do pageserver restarts and
migration.
## Future Work
- The control plane should make the initial lease request through HTTP
when creating a static endpoint. This is currently only done in
`neon_local`.
Signed-off-by: Yuchen Liang <yuchen@neon.tech>
cargo update ciborium iana-time-zone lazy_static schannel uuid
cargo update hyper@0.14
cargo update --precise 2.9.7 ureq
It might be worthwhile just update all our dependencies at some point,
but this is aimed at pruning the dependency tree, to make the build a
little faster. That's also why I didn't update ureq to the latest
version: that would've added a dependency to yet another version of
rustls.
PR #7782 set the dependency in Cargo.toml to 'master', and locked the
version to commit that contained a specific fix, because we needed the
fix before it was included in a versioned release. The fix was later
included in parquet crate version 52.0.0, so we can now switch back to
using a released version. The latest release is 53.0.0, switch straight
to that.
---------
Co-authored-by: Conrad Ludgate <conradludgate@gmail.com>
I wanted to use some features from the newer version. The PR that needed
the new version is not ready yet (and might never be), but seems nice to
stay up in any case.
We modified the crate in an incompatible way and upgraded to the new
version in PR #8076. However, it was reverted in #8654. The revert
reverted the Cargo.lock reference to it, but since Cargo.toml still
points to the (tip of the) 'neon' branch, every time you make any other
unrelated changes to Cargo.toml, it also tries to update the
rust-postgres crates to the tip of the 'neon' branch again, which
doesn't work.
To fix, lock the crates to the exact commit SHA that works.
This PR simplifies the pageserver configuration parsing as follows:
* introduce the `pageserver_api::config::ConfigToml` type
* implement `Default` for `ConfigToml`
* use serde derive to do the brain-dead leg-work of processing the toml
document
* use `serde(default)` to fill in default values
* in `pageserver` crate:
* use `toml_edit` to deserialize the pageserver.toml string into a
`ConfigToml`
* `PageServerConfig::parse_and_validate` then
* consumes the `ConfigToml`
* destructures it exhaustively into its constituent fields
* constructs the `PageServerConfig`
The rules are:
* in `ConfigToml`, use `deny_unknown_fields` everywhere
* static default values go in `pageserver_api`
* if there cannot be a static default value (e.g. which default IO
engine to use, because it depends on the runtime), make the field in
`ConfigToml` an `Option`
* if runtime-augmentation of a value is needed, do that in
`parse_and_validate`
* a good example is `virtual_file_io_engine` or `l0_flush`, both of
which need to execute code to determine the effective value in
`PageServerConf`
The benefits:
* massive amount of brain-dead repetitive code can be deleted
* "unused variable" compile-time errors when removing a config value,
due to the exhaustive destructuring in `parse_and_validate`
* compile-time errors guide you when adding a new config field
Drawbacks:
* serde derive is sometimes a bit too magical
* `deny_unknown_fields` is easy to miss
Future Work / Benefits:
* make `neon_local` use `pageserver_api` to construct `ConfigToml` and
write it to `pageserver.toml`
* This provides more type safety / coompile-time errors than the current
approach.
### Refs
Fixes#3682
### Future Work
* `remote_storage` deser doesn't reject unknown fields
https://github.com/neondatabase/neon/issues/8915
* clean up `libs/pageserver_api/src/config.rs` further
* break up into multiple files, at least for tenant config
* move `models` as appropriate / refine distinction between config and
API models / be explicit about when it's the same
* use `pub(crate)` visibility on `mod defaults` to detect stale values
Removes additional async_trait usages from safekeeper and neon_local.
Also removes now redundant dependencies of the `async_trait` crate.
cc earlier work: #6305, #6464, #7303, #7342, #7212, #8296
In proxy I switched to a leaky-bucket impl using the GCRA algorithm. I
figured I could share the code with pageserver and remove the
leaky_bucket crate dependency with some very basic tokio timers and
queues for fairness.
The underlying algorithm should be fairly clear how it works from the
comments I have left in the code.
---
In benchmarking pageserver, @problame found that the new implementation
fixes a getpage throughput discontinuity in pageserver under the
`pagebench get-page-latest-lsn` benchmark with the clickbench dataset
(`test_perf_olap.py`).
The discontinuity is that for any of `--num-clients={2,3,4}`, getpage
throughput remains 10k.
With `--num-clients=5` and greater, getpage throughput then jumps to the
configured 20k rate limit.
With the changes in this PR, the discontinuity is gone, and we scale
throughput linearly to `--num-clients` until the configured rate limit.
More context in
https://github.com/neondatabase/cloud/issues/16886#issuecomment-2315257641.
closes https://github.com/neondatabase/cloud/issues/16886
---------
Co-authored-by: Joonas Koivunen <joonas@neon.tech>
Co-authored-by: Christian Schwarz <christian@neon.tech>
Part of [Epic: Bypass PageCache for user data
blocks](https://github.com/neondatabase/neon/issues/7386).
# Problem
`InMemoryLayer` still uses the `PageCache` for all data stored in the
`VirtualFile` that underlies the `EphemeralFile`.
# Background
Before this PR, `EphemeralFile` is a fancy and (code-bloated) buffered
writer around a `VirtualFile` that supports `blob_io`.
The `InMemoryLayerInner::index` stores offsets into the `EphemeralFile`.
At those offset, we find a varint length followed by the serialized
`Value`.
Vectored reads (`get_values_reconstruct_data`) are not in fact vectored
- each `Value` that needs to be read is read sequentially.
The `will_init` bit of information which we use to early-exit the
`get_values_reconstruct_data` for a given key is stored in the
serialized `Value`, meaning we have to read & deserialize the `Value`
from the `EphemeralFile`.
The L0 flushing **also** needs to re-determine the `will_init` bit of
information, by deserializing each value during L0 flush.
# Changes
1. Store the value length and `will_init` information in the
`InMemoryLayer::index`. The `EphemeralFile` thus only needs to store the
values.
2. For `get_values_reconstruct_data`:
- Use the in-memory `index` figures out which values need to be read.
Having the `will_init` stored in the index enables us to do that.
- View the EphemeralFile as a byte array of "DIO chunks", each 512 bytes
in size (adjustable constant). A "DIO chunk" is the minimal unit that we
can read under direct IO.
- Figure out which chunks need to be read to retrieve the serialized
bytes for thes values we need to read.
- Coalesce chunk reads such that each DIO chunk is only read once to
serve all value reads that need data from that chunk.
- Merge adjacent chunk reads into larger
`EphemeralFile::read_exact_at_eof_ok` of up to 128k (adjustable
constant).
3. The new `EphemeralFile::read_exact_at_eof_ok` fills the IO buffer
from the underlying VirtualFile and/or its in-memory buffer.
4. The L0 flush code is changed to use the `index` directly, `blob_io`
5. We can remove the `ephemeral_file::page_caching` construct now.
The `get_values_reconstruct_data` changes seem like a bit overkill but
they are necessary so we issue the equivalent amount of read system
calls compared to before this PR where it was highly likely that even if
the first PageCache access was a miss, remaining reads within the same
`get_values_reconstruct_data` call from the same `EphemeralFile` page
were a hit.
The "DIO chunk" stuff is truly unnecessary for page cache bypass, but,
since we're working on [direct
IO](https://github.com/neondatabase/neon/issues/8130) and
https://github.com/neondatabase/neon/issues/8719 specifically, we need
to do _something_ like this anyways in the near future.
# Alternative Design
The original plan was to use the `vectored_blob_io` code it relies on
the invariant of Delta&Image layers that `index order == values order`.
Further, `vectored_blob_io` code's strategy for merging IOs is limited
to adjacent reads. However, with direct IO, there is another level of
merging that should be done, specifically, if multiple reads map to the
same "DIO chunk" (=alignment-requirement-sized and -aligned region of
the file), then it's "free" to read the chunk into an IO buffer and
serve the two reads from that buffer.
=> https://github.com/neondatabase/neon/issues/8719
# Testing / Performance
Correctness of the IO merging code is ensured by unit tests.
Additionally, minimal tests are added for the `EphemeralFile`
implementation and the bit-packed `InMemoryLayerIndexValue`.
Performance testing results are presented below.
All pref testing done on my M2 MacBook Pro, running a Linux VM.
It's a release build without `--features testing`.
We see definitive improvement in ingest performance microbenchmark and
an ad-hoc microbenchmark for getpage against InMemoryLayer.
```
baseline: commit 7c74112b2a origin/main
HEAD: ef1c55c52e
```
<details>
```
cargo bench --bench bench_ingest -- 'ingest 128MB/100b seq, no delta'
baseline
ingest-small-values/ingest 128MB/100b seq, no delta
time: [483.50 ms 498.73 ms 522.53 ms]
thrpt: [244.96 MiB/s 256.65 MiB/s 264.73 MiB/s]
HEAD
ingest-small-values/ingest 128MB/100b seq, no delta
time: [479.22 ms 482.92 ms 487.35 ms]
thrpt: [262.64 MiB/s 265.06 MiB/s 267.10 MiB/s]
```
</details>
We don't have a micro-benchmark for InMemoryLayer and it's quite
cumbersome to add one. So, I did manual testing in `neon_local`.
<details>
```
./target/release/neon_local stop
rm -rf .neon
./target/release/neon_local init
./target/release/neon_local start
./target/release/neon_local tenant create --set-default
./target/release/neon_local endpoint create foo
./target/release/neon_local endpoint start foo
psql 'postgresql://cloud_admin@127.0.0.1:55432/postgres'
psql (13.16 (Debian 13.16-0+deb11u1), server 15.7)
CREATE TABLE wal_test (
id SERIAL PRIMARY KEY,
data TEXT
);
DO $$
DECLARE
i INTEGER := 1;
BEGIN
WHILE i <= 500000 LOOP
INSERT INTO wal_test (data) VALUES ('data');
i := i + 1;
END LOOP;
END $$;
-- => result is one L0 from initdb and one 137M-sized ephemeral-2
DO $$
DECLARE
i INTEGER := 1;
random_id INTEGER;
random_record wal_test%ROWTYPE;
start_time TIMESTAMP := clock_timestamp();
selects_completed INTEGER := 0;
min_id INTEGER := 1; -- Minimum ID value
max_id INTEGER := 100000; -- Maximum ID value, based on your insert range
iters INTEGER := 100000000; -- Number of iterations to run
BEGIN
WHILE i <= iters LOOP
-- Generate a random ID within the known range
random_id := min_id + floor(random() * (max_id - min_id + 1))::int;
-- Select the row with the generated random ID
SELECT * INTO random_record
FROM wal_test
WHERE id = random_id;
-- Increment the select counter
selects_completed := selects_completed + 1;
-- Check if a second has passed
IF EXTRACT(EPOCH FROM clock_timestamp() - start_time) >= 1 THEN
-- Print the number of selects completed in the last second
RAISE NOTICE 'Selects completed in last second: %', selects_completed;
-- Reset counters for the next second
selects_completed := 0;
start_time := clock_timestamp();
END IF;
-- Increment the loop counter
i := i + 1;
END LOOP;
END $$;
./target/release/neon_local stop
baseline: commit 7c74112b2a origin/main
NOTICE: Selects completed in last second: 1864
NOTICE: Selects completed in last second: 1850
NOTICE: Selects completed in last second: 1851
NOTICE: Selects completed in last second: 1918
NOTICE: Selects completed in last second: 1911
NOTICE: Selects completed in last second: 1879
NOTICE: Selects completed in last second: 1858
NOTICE: Selects completed in last second: 1827
NOTICE: Selects completed in last second: 1933
ours
NOTICE: Selects completed in last second: 1915
NOTICE: Selects completed in last second: 1928
NOTICE: Selects completed in last second: 1913
NOTICE: Selects completed in last second: 1932
NOTICE: Selects completed in last second: 1846
NOTICE: Selects completed in last second: 1955
NOTICE: Selects completed in last second: 1991
NOTICE: Selects completed in last second: 1973
```
NB: the ephemeral file sizes differ by ca 1MiB, ours being 1MiB smaller.
</details>
# Rollout
This PR changes the code in-place and is not gated by a feature flag.
This removes workspace hack from all libs, not from any binaries. This
does not change the behaviour of the hack.
Running
```
cargo clean
cargo build --release --bin proxy
```
Before this change took 5m16s. After this change took 3m3s. This is
because this allows the build to be parallelisable much more.
basic JWT implementation that caches JWKs and verifies signatures.
this code is currently not reachable from proxy, I just wanted to get
something merged in.
This reverts #8076 - which was already reverted from the release branch
since forever (it would have been a breaking change to release for all
users who currently set TimeZone options). It's causing conflicts now so
we should revert it here as well.
## Problem
1. Hard to correlate startup parameters with the endpoint that provided
them.
2. Some configurations are not needed in the `ProxyConfig` struct.
## Summary of changes
Because of some borrow checker fun, I needed to switch to an
interior-mutability implementation of our `RequestMonitoring` context
system. Using https://docs.rs/try-lock/latest/try_lock/ as a cheap lock
for such a use-case (needed to be thread safe).
Removed the lock of each startup message, instead just logging only the
startup params in a successful handshake.
Also removed from values from `ProxyConfig` and kept as arguments.
(needed for local-proxy config)
Chaos injection bridges the gap between automated testing (where we do
lots of different things with small, short-lived tenants), and staging
(where we do many fewer things, but with larger, long-lived tenants).
This PR adds a first type of chaos which isn't really very chaotic: it's
live migration of tenants between healthy pageservers. This nevertheless
provides continuous checks that things like clean, prompt shutdown of
tenants works for realistically deployed pageservers with realistically
large tenants.
## Problem
We recently added a "visibility" state to layers, but nothing
initializes it.
Part of:
- #8398
## Summary of changes
- Add a dependency on `range-set-blaze`, which is used as a fast
incrementally updated alternative to KeySpace. We could also use this to
replace the internals of KeySpaceRandomAccum if we wanted to. Writing a
type that does this kind of "BtreeMap & merge overlapping entries" thing
isn't super complicated, but no reason to write this ourselves when
there's a third party impl available.
- Add a function to layermap to calculate visibilities for each layer
- Add a function to Timeline to call into layermap and then apply these
visibilities to the Layer objects.
- Invoke the calculation during startup, after image layer creations,
and when removing branches. Branch removal and image layer creation are
the two ways that a layer can go from Visible to Covered.
- Add unit test & benchmark for the visibility calculation
- Expose `pageserver_visible_physical_size` metric, which should always
be <= `pageserver_remote_physical_size`.
- This metric will feed into the /v1/utilization endpoint later: the
visible size indicates how much space we would like to use on this
pageserver for this tenant.
- When `pageserver_visible_physical_size` is greater than
`pageserver_resident_physical_size`, this is a sign that the tenant has
long-idle branches, which result in layers that are visible in
principle, but not used in practice.
This does not keep visibility hints up to date in all cases:
particularly, when creating a child timeline, any previously covered
layers will not get marked Visible until they are accessed.
Updates after image layer creation could be implemented as more of a
special case, but this would require more new code: the existing depth
calculation code doesn't maintain+yield the list of deltas that would be
covered by an image layer.
## Performance
This operation is done rarely (at startup and at timeline deletion), so
needs to be efficient but not ultra-fast.
There is a new `visibility` bench that measures runtime for a synthetic
100k layers case (`sequential`) and a real layer map (`real_map`) with
~26k layers.
The benchmark shows runtimes of single digit milliseconds (on a ryzen
7950). This confirms that the runtime shouldn't be a problem at startup
(as we already incur S3-level latencies there), but that it's slow
enough that we definitely shouldn't call it more often than necessary,
and it may be worthwhile to optimize further later (things like: when
removing a branch, only bother scanning layers below the branchpoint)
```
visibility/sequential time: [4.5087 ms 4.5894 ms 4.6775 ms]
change: [+2.0826% +3.9097% +5.8995%] (p = 0.00 < 0.05)
Performance has regressed.
Found 24 outliers among 100 measurements (24.00%)
2 (2.00%) high mild
22 (22.00%) high severe
min: 0/1696070, max: 93/1C0887F0
visibility/real_map time: [7.0796 ms 7.0832 ms 7.0871 ms]
change: [+0.3900% +0.4505% +0.5164%] (p = 0.00 < 0.05)
Change within noise threshold.
Found 4 outliers among 100 measurements (4.00%)
3 (3.00%) high mild
1 (1.00%) high severe
min: 0/1696070, max: 93/1C0887F0
visibility/real_map_many_branches
time: [4.5285 ms 4.5355 ms 4.5434 ms]
change: [-1.0012% -0.8004% -0.5969%] (p = 0.00 < 0.05)
Change within noise threshold.
```
Before, we had four versions of linux-raw-sys in our dependency graph:
```
linux-raw-sys@0.1.4
linux-raw-sys@0.3.8
linux-raw-sys@0.4.13
linux-raw-sys@0.6.4
```
now it's only two:
```
linux-raw-sys@0.4.13
linux-raw-sys@0.6.4
```
The changes in this PR are minimal. In order to get to its state one
only has to update procfs in Cargo.toml to 0.16 and do `cargo update -p
tempfile -p is-terminal -p prometheus`.
Part of #8128, followed by #8502.
## Problem
Currently we lack mechanism to alert unhealthy `scan_metadata` status if
we start running this scrubber command as part of a cronjob. With the
storage controller client introduced to storage scrubber in #8196, it is
viable to set up alert by storing health status in the storage
controller database.
We intentionally do not store the full output to the database as the
json blobs potentially makes the table really huge. Instead, only a
health status and a timestamp recording the last time metadata health
status is posted on a tenant shard.
Signed-off-by: Yuchen Liang <yuchen@neon.tech>
## Problem
LayerAccessStats contains a lot of detail that we don't use: short
histories of most recent accesses, specifics on what kind of task
accessed a layer, etc. This is all stored inside a Mutex, which is
locked every time something accesses a layer.
## Summary of changes
- Store timestamps at a very low resolution (to the nearest second),
sufficient for use on the timescales of eviction.
- Pack access time and last residence change time into a single u64
- Use the high bits of the u64 for other flags, including the new layer
visibility concept.
- Simplify the external-facing model for access stats to just include
what we now track.
Note that the `HistoryBufferWithDropCounter` is removed here because it
is no longer used. I do not dislike this type, we just happen not to use
it for anything else at present.
Co-authored-by: Christian Schwarz <christian@neon.tech>
This adds the ability to list many prefixes in a streaming fashion to
both the `RemoteStorage` trait as well as `GenericRemoteStorage`.
* The `list` function of the `RemoteStorage` trait is implemented by
default in terms of `list_streaming`.
* For the production users (S3, Azure), `list_streaming` is implemented
and the default `list` implementation is used.
* For `LocalFs`, we keep the `list` implementation and make
`list_streaming` call it.
The `list_streaming` function is implemented for both S3 and Azure.
A TODO for later is retries, which the scrubber currently has while the
`list_streaming` implementations lack them.
part of #8457 and #7547
