From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 5CC7665359 for ; Wed, 22 Jul 2020 16:16:52 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 0CDA2213AF for ; Wed, 22 Jul 2020 16:16:22 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [212.186.127.180]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id 68FED213A1 for ; Wed, 22 Jul 2020 16:16:21 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 11C2643131 for ; Wed, 22 Jul 2020 16:16:21 +0200 (CEST) To: Proxmox Backup Server development discussion , Stefan Reiter References: <20200722135625.23653-1-s.reiter@proxmox.com> <20200722135625.23653-2-s.reiter@proxmox.com> From: Thomas Lamprecht Message-ID: <05152997-427c-2cb9-014d-068c74935434@proxmox.com> Date: Wed, 22 Jul 2020 16:16:20 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:79.0) Gecko/20100101 Thunderbird/79.0 MIME-Version: 1.0 In-Reply-To: <20200722135625.23653-2-s.reiter@proxmox.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL 0.008 Adjusted score from AWL reputation of From: address KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment NICE_REPLY_A -0.001 Looks like a legit reply (A) RCVD_IN_DNSWL_MED -2.3 Sender listed at https://www.dnswl.org/, medium trust SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [index.rs] Subject: Re: [pbs-devel] [PATCH v2 backup 1/5] add and implement chunk_from_offset for IndexFile 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: , X-List-Received-Date: Wed, 22 Jul 2020 14:16:52 -0000 On 22.07.20 15:56, Stefan Reiter wrote: > Necessary for byte-wise seeking through chunks in an index. > > Signed-off-by: Stefan Reiter > --- > src/backup/dynamic_index.rs | 18 ++++++++++++++++++ > src/backup/fixed_index.rs | 11 +++++++++++ > src/backup/index.rs | 3 +++ > 3 files changed, 32 insertions(+) > > diff --git a/src/backup/dynamic_index.rs b/src/backup/dynamic_index.rs > index 4907fe1f..887b7cf3 100644 > --- a/src/backup/dynamic_index.rs > +++ b/src/backup/dynamic_index.rs > @@ -216,6 +216,24 @@ impl IndexFile for DynamicIndexReader { > digest: self.index[pos].digest.clone(), > }) > } > + > + fn chunk_from_offset(&self, offset: u64) -> Option<(usize, u64)> { > + let end_idx = self.index.len() - 1; > + let end = self.chunk_end(end_idx); > + let found_idx = self.binary_search(0, 0, end_idx, end, offset); > + let found_idx = match found_idx { > + Ok(i) => i, > + Err(_) => return None > + }; > + > + let found_start = if found_idx == 0 { > + 0 > + } else { > + self.chunk_end(found_idx - 1) > + }; > + > + Some((found_idx, offset - found_start)) > + } > } > > struct CachedChunk { > diff --git a/src/backup/fixed_index.rs b/src/backup/fixed_index.rs > index 73d0dad0..b7e785d6 100644 > --- a/src/backup/fixed_index.rs > +++ b/src/backup/fixed_index.rs > @@ -219,6 +219,17 @@ impl IndexFile for FixedIndexReader { > > (csum, chunk_end) > } > + > + fn chunk_from_offset(&self, offset: u64) -> Option<(usize, u64)> { > + if offset >= self.size { > + return None; > + } > + > + Some(( > + (offset / self.chunk_size as u64) as usize, > + offset % self.chunk_size as u64 modulo is really slow, but isn't chunk_size always a 2^x and thus we can do the same here as we do in other places: offset & (self.chunk_size - 1) > + )) > + } > } > > pub struct FixedIndexWriter { > diff --git a/src/backup/index.rs b/src/backup/index.rs > index efdf3b54..2eab8524 100644 > --- a/src/backup/index.rs > +++ b/src/backup/index.rs > @@ -22,6 +22,9 @@ pub trait IndexFile { > fn index_bytes(&self) -> u64; > fn chunk_info(&self, pos: usize) -> Option; > > + /// Get the chunk index and the relative offset within it for a byte offset > + fn chunk_from_offset(&self, offset: u64) -> Option<(usize, u64)>; > + > /// Compute index checksum and size > fn compute_csum(&self) -> ([u8; 32], u64); > >