Support direct use blob cache to run image #1436

zyfjeff · 2023-10-10T11:51:49Z

Relevant Issue (if applicable)

Details

In localfs mode, we can directly generate blob cache through -blob-cache-dir, in this case, Nydusd can directly use blob cache to start, but it manages the state of chunk through ChunkMap by default, and by default all chunks are not ready, and will go to babckend to download, for which I introduced disable_chunk_map config, to turn off the ability of ChunkMap, by default make all chunks are ready, although Nydusd will still visit the backend to verify the validity of the blob when initializing the backend. it requires that the original nydus blob must exist, I introduced use_cache_only config to disable Nydusd access backend

add disable_chunk_map to disable ChunkMap func
add use_cache_only to disable nydusd access backend

Types of changes

Bug fix (non-breaking change which fixes an issue)
New feature (non-breaking change which adds functionality)
Breaking change (fix or feature that would cause existing functionality to change)
Documentation Update (if none of the other choices apply)

Checklist

I have updated the documentation accordingly.
I have added tests to cover my changes.

zyfjeff · 2023-10-10T11:52:09Z

Ping @jiangliu

codecov · 2023-10-10T12:38:44Z

Codecov Report

Merging #1436 (a484d43) into master (002b2f2) will decrease coverage by 0.12%.
The diff coverage is 7.96%.

@@            Coverage Diff             @@
##           master    #1436      +/-   ##
==========================================
- Coverage   54.85%   54.74%   -0.12%     
==========================================
  Files         123      124       +1     
  Lines       40477    40584     +107     
  Branches    40477    40584     +107     
==========================================
+ Hits        22204    22217      +13     
- Misses      17034    17130      +96     
+ Partials     1239     1237       -2

Files	Coverage Δ
storage/src/backend/mod.rs	`56.07% <ø> (ø)`
api/src/config.rs	`72.23% <20.00%> (+0.25%)`	⬆️
storage/src/cache/filecache/mod.rs	`66.66% <33.33%> (-0.60%)`	⬇️
storage/src/factory.rs	`36.30% <40.00%> (+0.53%)`	⬆️
storage/src/cache/state/noop_chunk_map.rs	`5.88% <4.44%> (-27.46%)`	⬇️
storage/src/backend/noop.rs	`0.00% <0.00%> (ø)`

... and 3 files with indirect coverage changes

smoke/tests/blobcache_test.go

storage/src/backend/mod.rs

storage/src/backend/noop.rs

storage/src/factory.rs

storage/src/cache/state/noop_chunk_map.rs

zyfjeff · 2023-10-11T02:11:54Z

thanks, It has all been fixed, PTAL @jiangliu

imeoer · 2023-10-19T02:35:29Z

api/src/config.rs

@@ -755,6 +756,9 @@ pub struct FileCacheConfig {
    /// Key for data encryption, a heximal representation of [u8; 32].
    #[serde(default)]
    pub encryption_key: String,
+    /// disbale chunk map, it is assumed that all data is ready
+    #[serde(default)]
+    pub disable_chunk_map: bool,


Is this option similar to disable_indexed_map ? And should we export the option to the user?

imeoer · 2023-10-19T02:38:07Z

api/src/config.rs

@@ -842,6 +846,9 @@ pub struct RafsConfigV2 {
    /// Filesystem prefetching configuration.
    #[serde(default)]
    pub prefetch: PrefetchConfigV2,
+    // Only use cache, don't access the backend
+    #[serde(default)]
+    pub use_cache_only: bool,


The option should be put into the device.cache ?

In localfs mode, we can directly generate blob cache through -blob-cache-dir, in this case, Nydusd can directly use blob cache to start, but it manages the state of chunk through ChunkMap by default, and by default all chunks are not ready, and will go to babckend to download, for which I introduced disable_chunk_map config, to turn off the ability of ChunkMap, by default make all chunks are ready, although Nydusd will still visit the backend to verify the validity of the blob when initializing the backend. it requires that the original nydus blob must exist, I introduced use_cache_only config to disable Nydusd access backend 1. add disable_chunk_map to disable ChunkMap func 2. add use_cache_only to disable nydusd access backend Signed-off-by: zyfjeff <[email protected]>

bergwolf · 2023-11-01T03:50:18Z

api/src/config.rs

@@ -1260,6 +1267,9 @@ impl TryFrom<&BackendConfig> for BackendConfigV2 {
            "registry" => {
                config.registry = Some(serde_json::from_value(value.backend_config.clone())?);
            }
+            "noop" => {


Why do you need noop instead of using the localfs backend? You can amend localfs to work w/o the chunkmap. There is no need to introduce a new backend type for this IMO.

imeoer · 2024-06-18T06:56:56Z

Maybe close the PR if no more usage, we can still reopen it if necessary. cc @zyfjeff

zyfjeff requested a review from a team as a code owner October 10, 2023 11:51

zyfjeff requested review from liubogithub, imeoer and adamqqqplay and removed request for a team October 10, 2023 11:51

zyfjeff force-pushed the feature-cache-only branch from 765e342 to f9151d8 Compare October 10, 2023 12:33

zyfjeff force-pushed the feature-cache-only branch from f9151d8 to 18ba431 Compare October 10, 2023 12:48