@@ -22,7 +22,8 @@
import math
import os
import subprocess
-from typing import List
+import time
+from typing import List, Optional
import iotests
from iotests import qemu_img
@@ -195,12 +196,15 @@ class TestActiveMirror(iotests.QMPTestCase):
self.potential_writes_in_flight = False
-class TestThrottledWithNbdExport(iotests.QMPTestCase):
+class TestThrottledWithNbdExportBase(iotests.QMPTestCase):
image_len = 128 * 1024 * 1024 # MB
- iops = 16
+ iops: Optional[int] = None
background_processes: List['subprocess.Popen[str]'] = []
def setUp(self):
+ # Must be set by subclasses
+ self.assertIsNotNone(self.iops)
+
qemu_img('create', '-f', iotests.imgfmt, source_img, '128M')
qemu_img('create', '-f', iotests.imgfmt, target_img, '128M')
@@ -284,6 +288,10 @@ class TestThrottledWithNbdExport(iotests.QMPTestCase):
os.remove(source_img)
os.remove(target_img)
+
+class TestLowThrottledWithNbdExport(TestThrottledWithNbdExportBase):
+ iops = 16
+
def testUnderLoad(self):
'''
Throttle the source node, then issue a whole bunch of external requests
@@ -370,6 +378,45 @@ class TestThrottledWithNbdExport(iotests.QMPTestCase):
self.assertGreater(start_remaining - end_remaining, 0)
+class TestHighThrottledWithNbdExport(TestThrottledWithNbdExportBase):
+ iops = 1024
+
+ def testActiveOnCreation(self):
+ '''
+ Issue requests on the mirror source node right as the mirror is
+ instated. It's possible that requests occur before the actual job is
+ created, but after the node has been put into the graph. Write
+ requests across the node must in that case be forwarded to the source
+ node without attempting to mirror them (there is no job object yet, so
+ attempting to access it would cause a segfault).
+ We do this with a lightly throttled node (i.e. quite high IOPS limit).
+ Using throttling seems to increase reproductivity, but if the limit is
+ too low, all requests allowed per second will be submitted before
+ mirror_start_job() gets to the problematic point.
+ '''
+
+ # Let qemu-img bench create write requests (enough for two seconds on
+ # the virtual clock)
+ bench_args = ['bench', '-w', '-d', '1024', '-f', 'nbd',
+ '-c', str(self.iops * 2), self.nbd_url]
+ p = iotests.qemu_tool_popen(iotests.qemu_img_args + bench_args)
+ self.background_processes += [p]
+
+ # Give qemu-img bench time to start up and issue requests
+ time.sleep(1.0)
+ # Flush the request queue, so new requests can come in right as we
+ # start blockdev-mirror
+ self.vm.qtest(f'clock_step {1 * 1000 * 1000 * 1000}')
+
+ result = self.vm.qmp('blockdev-mirror',
+ job_id='mirror',
+ device='source-node',
+ target='target-node',
+ sync='full',
+ copy_mode='write-blocking')
+ self.assert_qmp(result, 'return', {})
+
+
if __name__ == '__main__':
iotests.main(supported_fmts=['qcow2', 'raw'],
supported_protocols=['file'])
@@ -1,5 +1,5 @@
-.....
+......
----------------------------------------------------------------------
-Ran 5 tests
+Ran 6 tests
OK