From 6a30f663d4c0b3c45a544d541e0c4e214b2473a1 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Sun, 17 Jan 2021 00:47:00 +0300 Subject: [PATCH] qapi: backup: disable copy_range by default Further commit will add a benchmark (scripts/simplebench/bench-backup.py), which will show that backup works better with async parallel requests (previous commit) and disabled copy_range. So, let's disable copy_range by default. Note: the option was added several commits ago with default to true, to follow old behavior (the feature was enabled unconditionally), and only now we are going to change the default behavior. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Max Reitz Message-Id: <20210116214705.822267-19-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz --- blockdev.c | 2 +- qapi/block-core.json | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/blockdev.c b/blockdev.c index 25aaacf253..93417f6302 100644 --- a/blockdev.c +++ b/blockdev.c @@ -2829,7 +2829,7 @@ static BlockJob *do_backup_common(BackupCommon *backup, { BlockJob *job = NULL; BdrvDirtyBitmap *bmap = NULL; - BackupPerf perf = { .use_copy_range = true, .max_workers = 64 }; + BackupPerf perf = { .max_workers = 64 }; int job_flags = JOB_DEFAULT; if (!backup->has_speed) { diff --git a/qapi/block-core.json b/qapi/block-core.json index abcd41ed63..9f555d5c1d 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -1377,7 +1377,7 @@ # Optional parameters for backup. These parameters don't affect # functionality, but may significantly affect performance. # -# @use-copy-range: Use copy offloading. Default true. +# @use-copy-range: Use copy offloading. Default false. # # @max-workers: Maximum number of parallel requests for the sustained background # copying process. Doesn't influence copy-before-write operations.