Blame SOURCES/0036-v2v-Disable-readahead-for-VMware-curl-sources-too-RH.patch

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From e12604349587b67b3b4c3d0b7b1779999460a93d Mon Sep 17 00:00:00 2001
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From: "Richard W.M. Jones" <rjones@redhat.com>
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Date: Fri, 19 Jun 2020 13:43:47 +0100
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Subject: [PATCH] v2v: Disable readahead for VMware curl sources too
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 (RHBZ#1848862).
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This appears to be the cause of timeouts during the conversion step
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where VMware VCenter server's Tomcat HTTPS server stops responding to
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requests (or rather, responds only with 503 errors).  The server later
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recovers and in fact because of the retry filter the conversion
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usually succeeds, but I found that we can avoid the problem by
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disabling readahead.
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(cherry picked from commit 9f4940068022d4e7abdfea6617b73a2b206f19aa)
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---
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 v2v/nbdkit_sources.ml | 8 ++++----
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 1 file changed, 4 insertions(+), 4 deletions(-)
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diff --git a/v2v/nbdkit_sources.ml b/v2v/nbdkit_sources.ml
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index f5e91911..7c177e35 100644
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--- a/v2v/nbdkit_sources.ml
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+++ b/v2v/nbdkit_sources.ml
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@@ -99,12 +99,12 @@ let common_create ?bandwidth ?extra_debug ?extra_env password
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   (* Adding the readahead filter is always a win for our access
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    * patterns.  If it doesn't exist don't worry.  However it
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-   * breaks VMware servers (RHBZ#1832805).
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+   * breaks VMware servers (RHBZ#1832805, RHBZ#1848862).
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    *)
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   let cmd =
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-    if plugin_name <> "vddk" then
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-      Nbdkit.add_filter_if_available cmd "readahead"
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-    else cmd in
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+    match plugin_name with
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+    | "vddk" | "curl" -> cmd
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+    | _ -> Nbdkit.add_filter_if_available cmd "readahead" in
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   (* Caching extents speeds up qemu-img, especially its consecutive
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    * block_status requests with req_one=1.
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-- 
446330
2.27.0
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