Don't use nbdkit-file-plugin cache=none when writing

Further performance fix for https://bugzilla.redhat.com/2011713

related: rhbz#2011713

0001-output-Don-t-use-nbdkit-file-plugin-cache-none-when-.patch

@@ -0,0 +1,57 @@
+From ac59d3b2310511b1537d408b675b19ec9a5d384e Mon Sep 17 00:00:00 2001
+From: "Richard W.M. Jones" <rjones@redhat.com>
+Date: Tue, 7 Dec 2021 12:53:41 +0000
+Subject: [PATCH] output: Don't use nbdkit-file-plugin cache=none when writing
+
+nbdkit-file-plugin flag cache=none is meant to ensure that the file
+plugin does not pollute the page cache.  However it doesn't yet work
+very well, especially for writing.  As you can see here:
+
+https://gitlab.com/nbdkit/nbdkit/-/blob/048d5b9818c88355e596824355269773e5c4f6ad/plugins/file/file.c#L594
+
+it is currently implemented by flushing the whole file (including
+parallel requests), and then evicting the data from the page cache.
+This implementation is naive.  (See nbdcopy copy/file-ops.c for a much
+better implementation.)
+
+This causes quite a considerable slow down when writing to a local
+file (eg -os local).  The penalty varies between machines and possibly
+kernels.  On my Fedora Rawhide AMD server with 12 cores and SSDs, the
+slow down is under 5%.  But on my RHEL 9 Intel NUC server with 2 cores
+and a hard disk, it makes a really huge difference, nearly doubling
+the total time taken.
+
+I left a note in the code that we should fix this in nbdkit and re-add
+this option or similar when it is working.
+
+I also removed the fadvise=sequential option.  This is associated with
+cache=none in the nbdkit documentation, and anyway we are not doing
+sequential writes.  (This makes no measurable difference in my testing)
+---
+ output/output.ml | 10 ++++++++--
+ 1 file changed, 8 insertions(+), 2 deletions(-)
+
+diff --git a/output/output.ml b/output/output.ml
+index 7e976508..f829fe43 100644
+--- a/output/output.ml
++++ b/output/output.ml
+@@ -98,8 +98,14 @@ let output_to_local_file ?(changeuid = fun f -> f ())
+      let cmd = Nbdkit.add_arg cmd "file" filename in
+      let cmd =
+        if Nbdkit.version nbdkit_config >= (1, 22, 0) then (
+-         let cmd = Nbdkit.add_arg cmd "fadvise" "sequential" in
+-         let cmd = Nbdkit.add_arg cmd "cache" "none" in
++         (* nbdkit 1.28 has a very naive implementation of
++          * page cache eviction.  We need to copy the one from
++          * nbdcopy copy/file-ops.c.  Until then do not use
++          * this flag because it causes a large slow down on
++          * some machines. XXX
++          *)
++         (*let cmd = Nbdkit.add_arg cmd "fadvise" "sequential" in
++           let cmd = Nbdkit.add_arg cmd "cache" "none" in*)
+          cmd
+        )
+        else cmd in
+-- 
+2.31.1
+

0002-RHEL-v2v-Select-correct-qemu-binary-for-o-qemu-mode-.patch

@@ -1,4 +1,4 @@
-From 950985cd43569d085b1198a15d9ffe0185e954a5 Mon Sep 17 00:00:00 2001
+From a0cc1fcb8f577802908887ed6cf98913f4260481 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Sun, 28 Sep 2014 19:14:43 +0100
 Subject: [PATCH] RHEL: v2v: Select correct qemu binary for -o qemu mode

0003-RHEL-v2v-Disable-the-qemu-boot-oo-qemu-boot-option-R.patch

@@ -1,4 +1,4 @@
-From 30dd7bf52be72eb2d4d638db89924a701a8290c3 Mon Sep 17 00:00:00 2001
+From 46ae00f83c2f4459fcdbf090d02a3f5cb4421fe9 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Tue, 30 Sep 2014 10:50:27 +0100
 Subject: [PATCH] RHEL: v2v: Disable the --qemu-boot / -oo qemu-boot option

0004-RHEL-Fix-list-of-supported-sound-cards-to-match-RHEL.patch

@@ -1,4 +1,4 @@
-From 8d76ce9a924775b20f5d7a92e2709393e80a3312 Mon Sep 17 00:00:00 2001
+From b12adf807a16e71764601f5912f98ead7839e25a Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Fri, 24 Apr 2015 09:45:41 -0400
 Subject: [PATCH] RHEL: Fix list of supported sound cards to match RHEL qemu

0005-RHEL-Fixes-for-libguestfs-winsupport.patch

@@ -1,4 +1,4 @@
-From 225d717b0bfc70d4eaacee8bb09dc4d8cfc3219e Mon Sep 17 00:00:00 2001
+From 836076de3059b12d54f098853bf5b35087885eeb Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Sun, 30 Aug 2015 03:21:57 -0400
 Subject: [PATCH] RHEL: Fixes for libguestfs-winsupport.

0006-RHEL-v2v-i-disk-force-VNC-as-display-RHBZ-1372671.patch

@@ -1,4 +1,4 @@
-From 105f5aa22cd03e480b63f61b56e7459db69d41c8 Mon Sep 17 00:00:00 2001
+From 9b570f662ac6e72abeec7271856a08c759a3bca7 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Thu, 2 Mar 2017 14:21:37 +0100
 Subject: [PATCH] RHEL: v2v: -i disk: force VNC as display (RHBZ#1372671)

0007-RHEL-v2v-do-not-mention-SUSE-Xen-hosts-RHBZ-1430203.patch

@@ -1,4 +1,4 @@
-From 8d8dcce022f27e5c82f0bb72fddf5b9329373761 Mon Sep 17 00:00:00 2001
+From 2a96ca52ae36874d333b199caea11594ad82638f Mon Sep 17 00:00:00 2001
 From: Pino Toscano <ptoscano@redhat.com>
 Date: Wed, 8 Mar 2017 11:03:40 +0100
 Subject: [PATCH] RHEL: v2v: do not mention SUSE Xen hosts (RHBZ#1430203)

0008-RHEL-point-to-KB-for-supported-v2v-hypervisors-guest.patch

@@ -1,4 +1,4 @@
-From 98e2603f7ff0a2cd9f23f80dd1d22f908a1a869d Mon Sep 17 00:00:00 2001
+From d3536cfb1a741b296cd904db303cb002cae4fbfd Mon Sep 17 00:00:00 2001
 From: Pino Toscano <ptoscano@redhat.com>
 Date: Tue, 26 Mar 2019 09:42:25 +0100
 Subject: [PATCH] RHEL: point to KB for supported v2v hypervisors/guests

0009-RHEL-Disable-o-glance.patch

@@ -1,4 +1,4 @@
-From e1f82d3ca83499a4fce6347664a277679c04db93 Mon Sep 17 00:00:00 2001
+From 608b966f2f41ccd3e500a16496b9ff1b456d99e0 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Wed, 30 Jun 2021 11:15:52 +0100
 Subject: [PATCH] RHEL: Disable -o glance

0010-RHEL-Remove-the-in-place-option.patch

@@ -1,4 +1,4 @@
-From c7de0b56ada81868aecd1c719bc3621109675b60 Mon Sep 17 00:00:00 2001
+From c4e64b06d8e92cf82fc1fee881876ffe45add057 Mon Sep 17 00:00:00 2001
 From: "Richard W.M. Jones" <rjones@redhat.com>
 Date: Thu, 2 Dec 2021 11:56:05 +0000
 Subject: [PATCH] RHEL: Remove the --in-place option

virt-v2v.spec

@@ -15,7 +15,7 @@
 Name:          virt-v2v
 Epoch:         1
 Version:       1.45.94
-Release:       1%{?dist}
+Release:       2%{?dist}
 Summary:       Convert a virtual machine to run on KVM
 
 License:       GPLv2+
@@ -51,15 +51,16 @@ ExclusiveArch: x86_64
 # Downstream (RHEL-only) patches.
 %if 0%{?rhel}
 # Patches.
-Patch0001:     0001-RHEL-v2v-Select-correct-qemu-binary-for-o-qemu-mode-.patch
-Patch0002:     0002-RHEL-v2v-Disable-the-qemu-boot-oo-qemu-boot-option-R.patch
-Patch0003:     0003-RHEL-Fix-list-of-supported-sound-cards-to-match-RHEL.patch
-Patch0004:     0004-RHEL-Fixes-for-libguestfs-winsupport.patch
-Patch0005:     0005-RHEL-v2v-i-disk-force-VNC-as-display-RHBZ-1372671.patch
-Patch0006:     0006-RHEL-v2v-do-not-mention-SUSE-Xen-hosts-RHBZ-1430203.patch
-Patch0007:     0007-RHEL-point-to-KB-for-supported-v2v-hypervisors-guest.patch
-Patch0008:     0008-RHEL-Disable-o-glance.patch
-Patch0009:     0009-RHEL-Remove-the-in-place-option.patch
+Patch0001:     0001-output-Don-t-use-nbdkit-file-plugin-cache-none-when-.patch
+Patch0002:     0002-RHEL-v2v-Select-correct-qemu-binary-for-o-qemu-mode-.patch
+Patch0003:     0003-RHEL-v2v-Disable-the-qemu-boot-oo-qemu-boot-option-R.patch
+Patch0004:     0004-RHEL-Fix-list-of-supported-sound-cards-to-match-RHEL.patch
+Patch0005:     0005-RHEL-Fixes-for-libguestfs-winsupport.patch
+Patch0006:     0006-RHEL-v2v-i-disk-force-VNC-as-display-RHBZ-1372671.patch
+Patch0007:     0007-RHEL-v2v-do-not-mention-SUSE-Xen-hosts-RHBZ-1430203.patch
+Patch0008:     0008-RHEL-point-to-KB-for-supported-v2v-hypervisors-guest.patch
+Patch0009:     0009-RHEL-Disable-o-glance.patch
+Patch0010:     0010-RHEL-Remove-the-in-place-option.patch
 %endif
 
 %if 0%{patches_touch_autotools}
@@ -300,11 +301,8 @@ popd
 
 
 %changelog
-* Tue Dec 07 2021 Richard W.M. Jones <rjones@redhat.com> - 1:1.45.94-1
-- New upstream development version 1.45.94 (preview of 2.0)
-
-* Fri Dec 03 2021 Richard W.M. Jones <rjones@redhat.com> - 1:1.45.93-1
-- Rebase to upstream 1.45.93.
+* Tue Dec 07 2021 Richard W.M. Jones <rjones@redhat.com> - 1:1.45.94-2
+- Rebase to upstream 1.45.94.
 - Change video type to VGA (instead of QXL).
 - Remove --in-place support properly.
 - Remove -o glance support properly.