Am 30.06.2016 um 17:59 schrieb Paolo Bonzini:
On 30/06/2016 13:08, Peter Lieven wrote:this fills up the allocationmap at iscsi_open. This helps to reduce the number of get_block_status requests during runtime significantly. Signed-off-by: Peter Lieven <p...@kamp.de> --- block/iscsi.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/block/iscsi.c b/block/iscsi.c index 0cdcedb..04fb0a3 100644 --- a/block/iscsi.c +++ b/block/iscsi.c @@ -1774,6 +1774,22 @@ static int iscsi_open(BlockDriverState *bs, QDict *options, int flags, iscsilun->block_size) >> BDRV_SECTOR_BITS; if (iscsilun->lbprz) { ret = iscsi_allocmap_init(iscsilun, bs->open_flags); + if (ret == 0) { + unsigned int max_reqs = 64; + int64_t sector_num = 0; + while (max_reqs-- && sector_num < bs->total_sectors) { + int n; + BlockDriverState *file; + ret = bdrv_get_block_status(bs, sector_num, + BDRV_REQUEST_MAX_SECTORS, + &n, &file); + if (ret < 0) { + break; + } + sector_num += n; + ret = 0; + } + } } }This can take a long time and the disks may not even be ever used. I don't think it's a good idea.
Sure, the target might stay unused, but why do you suspect its slow? Peter
