From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [IPv6:2a01:7e0:0:424::9]) by lore.proxmox.com (Postfix) with ESMTPS id D7D8A1FF187 for ; Mon, 3 Nov 2025 12:31:23 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 5187C1AA82; Mon, 3 Nov 2025 12:31:51 +0100 (CET) From: Christian Ebner To: pbs-devel@lists.proxmox.com Date: Mon, 3 Nov 2025 12:31:19 +0100 Message-ID: <20251103113120.239455-17-c.ebner@proxmox.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251103113120.239455-1-c.ebner@proxmox.com> References: <20251103113120.239455-1-c.ebner@proxmox.com> MIME-Version: 1.0 X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1762169486205 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.047 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: [pbs-devel] [PATCH proxmox-backup 16/17] GC: lock chunk marker before cleanup in phase 3 on s3 backends X-BeenThere: pbs-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox Backup Server development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Proxmox Backup Server development discussion Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: pbs-devel-bounces@lists.proxmox.com Sender: "pbs-devel" To make sure there is no race between atime check and deletion with possible re-insertion. By only acquiring the file lock if the chunk marker would be removed and double stating, the file locking penalty is avoided for the other cases. Signed-off-by: Christian Ebner --- pbs-datastore/src/chunk_store.rs | 28 +++++++++++++++++++++++++++- pbs-datastore/src/datastore.rs | 2 ++ 2 files changed, 29 insertions(+), 1 deletion(-) diff --git a/pbs-datastore/src/chunk_store.rs b/pbs-datastore/src/chunk_store.rs index 49687b2fa..08519fe2b 100644 --- a/pbs-datastore/src/chunk_store.rs +++ b/pbs-datastore/src/chunk_store.rs @@ -5,6 +5,7 @@ use std::sync::{Arc, Mutex}; use std::time::Duration; use anyhow::{bail, format_err, Context, Error}; +use hex::FromHex; use tracing::{info, warn}; use pbs_api_types::{DatastoreFSyncLevel, GarbageCollectionStatus}; @@ -22,7 +23,7 @@ use crate::data_blob::DataChunkBuilder; use crate::file_formats::{ COMPRESSED_BLOB_MAGIC_1_0, ENCRYPTED_BLOB_MAGIC_1_0, UNCOMPRESSED_BLOB_MAGIC_1_0, }; -use crate::DataBlob; +use crate::{DataBlob, LocalDatastoreLruCache}; /// File system based chunk store pub struct ChunkStore { @@ -366,6 +367,7 @@ impl ChunkStore { min_atime: i64, status: &mut GarbageCollectionStatus, worker: &dyn WorkerTaskContext, + cache: Option<&LocalDatastoreLruCache>, ) -> Result<(), Error> { // unwrap: only `None` in unit tests assert!(self.locker.is_some()); @@ -419,6 +421,30 @@ impl ChunkStore { bad, status, || { + if let Some(cache) = cache { + // never lock bad chunks + if filename.to_bytes().len() == 64 { + let digest = <[u8; 32]>::from_hex(filename.to_bytes())?; + match self.lock_chunk(&digest, Duration::from_secs(0)) { + Ok(_guard) => { + // don't remove if changed since locking + match fstatat( + Some(dirfd), + filename, + nix::fcntl::AtFlags::AT_SYMLINK_NOFOLLOW, + ) { + Ok(stat) if stat.st_atime < min_atime => { + let _ = cache.remove(&digest); + return Ok(()); + } + _ => return Ok(()), + } + } + Err(_) => return Ok(()), + } + } + } + unlinkat(Some(dirfd), filename, UnlinkatFlags::NoRemoveDir).map_err( |err| { format_err!( diff --git a/pbs-datastore/src/datastore.rs b/pbs-datastore/src/datastore.rs index beca72e9a..33d589b67 100644 --- a/pbs-datastore/src/datastore.rs +++ b/pbs-datastore/src/datastore.rs @@ -1733,6 +1733,7 @@ impl DataStore { min_atime, &mut tmp_gc_status, worker, + self.cache(), )?; } else { self.inner.chunk_store.sweep_unused_chunks( @@ -1740,6 +1741,7 @@ impl DataStore { min_atime, &mut gc_status, worker, + None, )?; } -- 2.47.3 _______________________________________________ pbs-devel mailing list pbs-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pbs-devel