[Libguestfs] Long running nbdkit tests

[Richard W.M. Jones]

I pushed a change which should reduce the time taken in the
test-cache-* and test-cow.sh tests.  Again note this is double TCG
which is the worst case for these tests and explains the excessively
long times which wouldn't be seen on a normal build system.

Updated results:

01:04:18 PASS: test-readahead
01:02:32 PASS: test-cow.sh
00:37:25 PASS: test-floppy.sh
00:34:57 PASS: test-shell
00:34:53 PASS: test-linuxdisk-copy-out.sh
00:33:57 PASS: test-partitioning3.sh
00:33:46 PASS: test-perl
00:33:38 PASS: test-partitioning5.sh
00:33:38 PASS: test-memory
00:33:28 PASS: test-ocaml
00:33:11 PASS: test-lua
00:32:33 PASS: test-tcl
00:32:16 PASS: test-offset
00:31:48 PASS: test-xz
00:31:47 PASS: test-xz-curl
00:30:19 PASS: test-partitioning2.sh
00:28:57 PASS: test-linuxdisk.sh
00:28:46 PASS: test-data
00:28:24 PASS: test-gzip
00:27:57 PASS: test-ext2
00:27:49 PASS: test-curl
00:27:16 PASS: test-iso.sh
00:25:56 PASS: test-nbd
[all others < 7 mins]

Analysis of what these tests do as in the previous email:

test-readahead             G   Fx2
test-cow.sh                Gx2
test-floppy.sh             G       Dx2
test-shell                 G
test-linuxdisk-copy-out.sh G       Dx4
test-partitioning3.sh      G
test-perl                  G
test-partitioning5.sh      G   F
test-memory                G
test-ocaml                 G
test-lua                   G
test-tcl                   G
test-offset                G
test-xz                    G
test-xz-curl               G           W
test-partitioning2.sh      G   F
test-linuxdisk.sh          G       D
test-data                  G
test-gzip                  G
test-ext2                  G
test-curl                  G           W
test-iso.sh                G
test-nbd                   G

D = using libguestfs download or similar APIs
F = using libguestfs "fill" APIs which write lots of data
G = guestfish/libguestfs
W = curl/webserver
xN = runs multiple times

test-readahead needs more work.  test-cow.sh is obdurately difficult
to test.  The others are good tests so there's probably not much we
can or should do to them.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
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