From 42786aef59d20814b703c2b94f2ef117199c5e83 Mon Sep 17 00:00:00 2001 From: Philippe Antoine Date: Thu, 16 Mar 2023 09:20:40 +0100 Subject: [PATCH] http2: faster when reducing dynamic headers size avoid quadratic complexity from removing the first element and copying all the contents a big number fo times. Ticket: #5909 (cherry picked from commit 9adb59bcdb61a06792bec1bee468a900ad5118f5) --- rust/src/http2/parser.rs | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/rust/src/http2/parser.rs b/rust/src/http2/parser.rs index 87ab117a50..d99efd95a6 100644 --- a/rust/src/http2/parser.rs +++ b/rust/src/http2/parser.rs @@ -564,13 +564,16 @@ fn http2_parse_headers_block_dynamic_size<'a>( if (maxsize2 as usize) < dyn_headers.max_size { //dyn_headers.max_size is updated later with all headers //may evict entries - while dyn_headers.current_size > (maxsize2 as usize) && dyn_headers.table.len() > 0 { + let mut toremove = 0; + while dyn_headers.current_size > (maxsize2 as usize) && toremove < dyn_headers.table.len() { // we check dyn_headers.table as we may be in best effort // because the previous maxsize was too big for us to retain all the headers - dyn_headers.current_size -= - 32 + dyn_headers.table[0].name.len() + dyn_headers.table[0].value.len(); - dyn_headers.table.remove(0); + dyn_headers.current_size -= 32 + + dyn_headers.table[toremove].name.len() + + dyn_headers.table[toremove].value.len(); + toremove += 1; } + dyn_headers.table.drain(0..toremove); } return Ok(( i3, -- 2.47.2