Add methods to insert new cache entries without using the cacher,
remove cache entries given their key and check if the cache contains
a key, marking it the most recently used one if it does.
These methods will be used to implement the local datastore cache
which stores the values (chunks) on the filesystem rather than
keeping track of them by storing them in-memory in the cache. The lru
cache will only be used to allow for fast lookup and keep track of
the lookup order.
Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
Reviewed-by: Hannes Laimer <h.laimer@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Add a callback function to be executed on evicted cache nodes. The
callback gets the key of the removed node, allowing to externally act
based on that value.
Since the callback might fail, extend the current LRU cache api to
return an error on insert, covering the error for the `removed`
callback.
Async lru cache, callsites and tests are adapted to include the
additional callback parameter accordingly.
Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
Reviewed-by: Hannes Laimer <h.laimer@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Since commit 1e7639bf ("fixup minimum lru capacity") the minimum
cache capacity is forced to be 1 to bypass edge cases for it being 0.
Explicitly mention this in the doc comment, as this behavior can be
unexpected.
Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
Add a boolean return type to LruCache::insert(), telling if the node
was already present in the cache or if it was newly inserted.
This will allow to use the LRU cache for garbage collection, where
it is required to skip atime updates for chunks already marked in
use.
That improves phase 1 garbage collection performance by avoiding,
multiple atime updates.
Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
these are only used by a single member at the moment, but we can move them to
the workspace to have a single location for version + base feature set
specification.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
besides harmonizing versions, the only global change is that the tokio-io
feature of pxar is now implied since its default anyway, instead of being
spelled out.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
pbs-buildcfg is the only one that needs to inherit the version as well, since
it stores it in the compiled crate.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
glibc's malloc has a misguided heuristic to detect transient allocations that
will just result in allocation sizes below 32 MiB never using mmap.
That it turn means that those relatively big allocations are on the heap where
cleanup and returning memory to the OS is harder to do and easier to be blocked
by long living, small allocations at the top (end) of the heap.
Observing the malloc size distribution in a file-level backup run:
@size:
[0] 14 | |
[1] 25214 |@@@@@ |
[2, 4) 9090 |@ |
[4, 8) 12987 |@@ |
[8, 16) 93453 |@@@@@@@@@@@@@@@@@@@@ |
[16, 32) 30255 |@@@@@@ |
[32, 64) 237445 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
[64, 128) 32692 |@@@@@@@ |
[128, 256) 22296 |@@@@ |
[256, 512) 16177 |@@@ |
[512, 1K) 5139 |@ |
[1K, 2K) 3352 | |
[2K, 4K) 214 | |
[4K, 8K) 1568 | |
[8K, 16K) 95 | |
[16K, 32K) 3457 | |
[32K, 64K) 3175 | |
[64K, 128K) 161 | |
[128K, 256K) 453 | |
[256K, 512K) 93 | |
[512K, 1M) 74 | |
[1M, 2M) 774 | |
[2M, 4M) 319 | |
[4M, 8M) 700 | |
[8M, 16M) 93 | |
[16M, 32M) 18 | |
We see that all allocations will be on the heap, and that while most
allocations are small, the relatively few big ones will still make up most of
the RSS and if blocked from being released back to the OS result in much higher
peak and average usage for the program than actually required.
Avoiding the "dynamic" mmap-threshold increasement algorithm and fixing it at
the original default of 128 KiB reduces RSS size by factor 10-20 when running
backups. As with memory mappings other mappings or the heap can never block
freeing the memory fully back to the OS.
But, the drawback of using mmap is more wasted space for unaligned or small
allocation sizes, and the fact that the kernel allegedly zeros out the data
before giving it to user space. The former doesn't really matter for us when
using it only for allocations bigger than 128 KiB, and the latter is a
trade-off, using 10 to 20 times less memory brings its own performance
improvement possibilities for the whole system after all ;-)
Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>
[ Thomas: added to comment & commit message + extra-empty-line fixes ]
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
this fixes the leaked memory for the cache, as we had only pointers
in the map/list which were freed, not the underlying chunks
moves the 'clear' implementation out of the trait bounds so that
Drop can reuse it
this is used e.g. for file download from a pxar
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
- imported pbs-api-types/src/common_regex.rs from old proxmox crate
- use hex crate to generate/parse hex digest
- remove all reference to proxmox crate (use proxmox-sys and
proxmox-serde instead)
Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>
