1 files changed, 0 insertions, 87 deletions

diff --git a/gitlab/issues/target_missing/host_missing/accel_missing/1362.toml b/gitlab/issues/target_missing/host_missing/accel_missing/1362.toml
deleted file mode 100644
index e4212013c..000000000
--- a/gitlab/issues/target_missing/host_missing/accel_missing/1362.toml
+++ /dev/null
@@ -1,87 +0,0 @@
-id = 1362
-title = "BLKZEROOUT ioct/write requests getting split a weird boundary (and for no apparent reason?)"
-state = "opened"
-created_at = "2022-12-11T15:38:46.884Z"
-closed_at = "n/a"
-labels = ["Storage"]
-url = "https://gitlab.com/qemu-project/qemu/-/issues/1362"
-host-os = "debian / live cd"
-host-arch = "n/a"
-qemu-version = "n/a"
-guest-os = "debian / live cd"
-guest-arch = "n/a"
-description = """i was investigating into some performance weirdness with passthrough/directly-mapped SAS vs. SATA disk, which seems to relate to detect_zeroes feature (see https://forum.proxmox.com/threads/disk-passthrough-performance-weirdness.118943/#post-516599 ).
-
-apparently, writing zeroes to passtrough/direct-mapped sas disk ( ST4000NM0034 ) in virtual machine is MUCH slower then sata disk ( HGST HDN728080AL ). 
-
-with detect_zeroes=on (default in proxmox) , qemu converts writes of zeroes into BLKZEROOUT ioctl issued to the target disk, and my sas disk is much much slower with this (<80MB/s in comparison to the sata disk with 200MB/s). 
-
-i found that the sas disk needs 0.01s on average for this ioctl to finish, whereas sata disk needs 0.004s.   
-
-writing zeroes to the device directly is at about 200MB/s for both of them, so having detect_zeroes=on a default does not seem to be an advantage on all circumstances.
-
-anyway, i have made a weird observation during analysis:
-
-inside the virtual machine, i'm writing to the virtual disk like this:
-
-```
-dd if=/dev/zero of=/dev/disk/by-id/scsi-0QEMU_QEMU_HARDDISK_drive-scsi1 bs=1024k count=1024 oflag=direct 
-
-(scsi-0QEMU_QEMU_HARDDISK_drive-scsi1 mapped to scsi-35000c500836b1c73 / SAS on the host, scsi-0QEMU_QEMU_HARDDISK_drive-scsi2 mapped to ata-HGST_HDN728080ALE604_VJGDNX5X )
-
-```
-
-on the HOST i'm attaching to the kvm process with strace , every time i issue the above dd inside VM, kvm/qemu process issues BLKZEROOUT to the device in a different way, i.e. either 
-
-- within a single ioctl at originating 1048576 byte size (=1024k)
-or
-- split into 2 ioctl with  1040384+8192(=1048576)
-or
-- split into 2 ioctl with 1044480+4096(=1048576)
-
-
-why does kvm/qemu sometimes split the write request and sometimes not ? and why at such a weird boundary just below 1Mb?
-
-
-i don't know if this is a bug, but at least it looks weird to me, that's why i'm reporting
-
-```
-
-root@pve:~/util-linux/sys-utils# strace -T -f -p 18897  -e trace=all 2>&1 |grep BLK|head
-[pid 65413] ioctl(19, BLKZEROOUT, [0, 1048576] <unfinished ...>
-[pid 65412] ioctl(19, BLKZEROOUT, [1048576, 1048576] <unfinished ...>
-[pid 65366] ioctl(19, BLKZEROOUT, [2097152, 1048576] <unfinished ...>
-[pid 65413] ioctl(19, BLKZEROOUT, [3145728, 1048576] <unfinished ...>
-[pid 65412] ioctl(19, BLKZEROOUT, [4194304, 1048576]) = 0 <0.011287>
-[pid 65366] ioctl(19, BLKZEROOUT, [5242880, 1048576]) = 0 <0.012025>
-[pid 65413] ioctl(19, BLKZEROOUT, [6291456, 1048576]) = 0 <0.011377>
-[pid 65412] ioctl(19, BLKZEROOUT, [7340032, 1048576] <unfinished ...>
-[pid 65366] ioctl(19, BLKZEROOUT, [8388608, 1048576] <unfinished ...>
-[pid 65413] ioctl(19, BLKZEROOUT, [9437184, 1048576]) = 0 <0.011705>
-
-# strace -T -f -p 18897  -e trace=all 2>&1 |grep BLK|head
-[pid 65878] ioctl(19, BLKZEROOUT, [0, 1040384] <unfinished ...>
-[pid 65413] ioctl(19, BLKZEROOUT, [1040384, 8192] <unfinished ...>
-[pid 65366] ioctl(19, BLKZEROOUT, [1048576, 1040384] <unfinished ...>
-[pid 65878] ioctl(19, BLKZEROOUT, [2088960, 8192] <unfinished ...>
-[pid 65413] ioctl(19, BLKZEROOUT, [2097152, 1040384] <unfinished ...>
-[pid 65366] ioctl(19, BLKZEROOUT, [3137536, 8192] <unfinished ...>
-[pid 65413] ioctl(19, BLKZEROOUT, [3145728, 1040384] <unfinished ...>
-[pid 65878] ioctl(19, BLKZEROOUT, [4186112, 8192] <unfinished ...>
-[pid 65366] ioctl(19, BLKZEROOUT, [4194304, 1040384] <unfinished ...>
-[pid 65413] ioctl(19, BLKZEROOUT, [5234688, 8192] <unfinished ...>
-
-root@pve:~/util-linux/sys-utils# strace -T -f -p 18897  -e trace=all 2>&1 |grep BLK|head
-[pid 66591] ioctl(19, BLKZEROOUT, [0, 1044480] <unfinished ...>
-[pid 66592] ioctl(19, BLKZEROOUT, [1044480, 4096] <unfinished ...>
-[pid 66593] ioctl(19, BLKZEROOUT, [1048576, 1044480] <unfinished ...>
-[pid 66584] ioctl(19, BLKZEROOUT, [2093056, 4096] <unfinished ...>
-[pid 66585] ioctl(19, BLKZEROOUT, [2097152, 1044480] <unfinished ...>
-[pid 66565] ioctl(19, BLKZEROOUT, [3141632, 4096] <unfinished ...>
-[pid 66591] ioctl(19, BLKZEROOUT, [3145728, 1044480] <unfinished ...>
-[pid 66592] ioctl(19, BLKZEROOUT, [4190208, 4096] <unfinished ...>
-[pid 66584] ioctl(19, BLKZEROOUT, [4194304, 1044480] <unfinished ...>
-[pid 66593] ioctl(19, BLKZEROOUT, [5238784, 4096] <unfinished ...
-```"""
-reproduce = "n/a"
-additional = "n/a"