From: Brian Warner Date: Wed, 11 Feb 2009 06:37:56 +0000 (-0700) Subject: #620: storage: allow mutable shares to be deleted, with a writev where new_length=0 X-Git-Tag: allmydata-tahoe-1.3.0~39 X-Git-Url: https://git.rkrishnan.org/components/com_hotproperty/%22doc.html/architecture.txt?a=commitdiff_plain;h=13a3ef5ec1f651cc44fec938e713f50017479ef0;p=tahoe-lafs%2Ftahoe-lafs.git #620: storage: allow mutable shares to be deleted, with a writev where new_length=0 --- diff --git a/src/allmydata/interfaces.py b/src/allmydata/interfaces.py index 524b75f0..96840029 100644 --- a/src/allmydata/interfaces.py +++ b/src/allmydata/interfaces.py @@ -207,7 +207,7 @@ class RIStorageServer(RemoteInterface): can be used to pre-allocate space for a series of upcoming writes, or truncate existing data. If the container is growing, new_length will be applied before datav. If the container is shrinking, it will be - applied afterwards. + applied afterwards. If new_length==0, the share will be deleted. The read vector is used to extract data from all known shares, *before* any writes have been applied. The same vector is used for diff --git a/src/allmydata/introducer/client.py b/src/allmydata/introducer/client.py index dac8bbd5..5781abce 100644 --- a/src/allmydata/introducer/client.py +++ b/src/allmydata/introducer/client.py @@ -34,6 +34,7 @@ class RemoteServiceConnector: "storage": { "http://allmydata.org/tahoe/protocols/storage/v1" : { "maximum-immutable-share-size": 2**32, "tolerates-immutable-read-overrun": False, + "delete-mutable-shares-with-zero-length-writev": False, }, "application-version": "unknown: no get_version()", }, diff --git a/src/allmydata/storage.py b/src/allmydata/storage.py index 8de5be3d..d5859c8f 100644 --- a/src/allmydata/storage.py +++ b/src/allmydata/storage.py @@ -963,6 +963,7 @@ class StorageServer(service.MultiService, Referenceable): version = { "http://allmydata.org/tahoe/protocols/storage/v1" : { "maximum-immutable-share-size": remaining_space, "tolerates-immutable-read-overrun": True, + "delete-mutable-shares-with-zero-length-writev": True, }, "application-version": str(allmydata.__version__), } @@ -1218,27 +1219,37 @@ class StorageServer(service.MultiService, Referenceable): for sharenum, share in shares.items(): read_data[sharenum] = share.readv(read_vector) + ownerid = 1 # TODO + expire_time = time.time() + 31*24*60*60 # one month + lease_info = LeaseInfo(ownerid, + renew_secret, cancel_secret, + expire_time, self.my_nodeid) + if testv_is_good: # now apply the write vectors for sharenum in test_and_write_vectors: (testv, datav, new_length) = test_and_write_vectors[sharenum] - if sharenum not in shares: - # allocate a new share - allocated_size = 2000 # arbitrary, really - share = self._allocate_slot_share(bucketdir, secrets, - sharenum, - allocated_size, - owner_num=0) - shares[sharenum] = share - shares[sharenum].writev(datav, new_length) - # and update the leases on all shares - ownerid = 1 # TODO - expire_time = time.time() + 31*24*60*60 # one month - lease_info = LeaseInfo(ownerid, - renew_secret, cancel_secret, - expire_time, self.my_nodeid) - for share in shares.values(): - share.add_or_renew_lease(lease_info) + if new_length == 0: + if sharenum in shares: + shares[sharenum].unlink() + else: + if sharenum not in shares: + # allocate a new share + allocated_size = 2000 # arbitrary, really + share = self._allocate_slot_share(bucketdir, secrets, + sharenum, + allocated_size, + owner_num=0) + shares[sharenum] = share + shares[sharenum].writev(datav, new_length) + # and update the lease + shares[sharenum].add_or_renew_lease(lease_info) + + if new_length == 0: + # delete empty bucket directories + if not os.listdir(bucketdir): + os.rmdir(bucketdir) + # all done self.add_latency("writev", time.time() - start) diff --git a/src/allmydata/test/test_storage.py b/src/allmydata/test/test_storage.py index 8557648c..a3b18af5 100644 --- a/src/allmydata/test/test_storage.py +++ b/src/allmydata/test/test_storage.py @@ -1150,6 +1150,50 @@ class MutableServer(unittest.TestCase): self.failUnlessRaises(IndexError, ss.remote_cancel_lease, "si2", "nonsecret") + def test_remove(self): + ss = self.create("test_remove") + self.allocate(ss, "si1", "we1", self._lease_secret.next(), + set([0,1,2]), 100) + readv = ss.remote_slot_readv + writev = ss.remote_slot_testv_and_readv_and_writev + secrets = ( self.write_enabler("we1"), + self.renew_secret("we1"), + self.cancel_secret("we1") ) + # delete sh0 by setting its size to zero + answer = writev("si1", secrets, + {0: ([], [], 0)}, + []) + # the answer should mention all the shares that existed before the + # write + self.failUnlessEqual(answer, (True, {0:[],1:[],2:[]}) ) + # but a new read should show only sh1 and sh2 + self.failUnlessEqual(readv("si1", [], [(0,10)]), + {1: [""], 2: [""]}) + + # delete sh1 by setting its size to zero + answer = writev("si1", secrets, + {1: ([], [], 0)}, + []) + self.failUnlessEqual(answer, (True, {1:[],2:[]}) ) + self.failUnlessEqual(readv("si1", [], [(0,10)]), + {2: [""]}) + + # delete sh2 by setting its size to zero + answer = writev("si1", secrets, + {2: ([], [], 0)}, + []) + self.failUnlessEqual(answer, (True, {2:[]}) ) + self.failUnlessEqual(readv("si1", [], [(0,10)]), + {}) + # and the bucket directory should now be gone + si = base32.b2a("si1") + # note: this is a detail of the storage server implementation, and + # may change in the future + prefix = si[:2] + prefixdir = os.path.join(self.workdir("test_remove"), "shares", prefix) + bucketdir = os.path.join(prefixdir, si) + self.failUnless(os.path.exists(prefixdir)) + self.failIf(os.path.exists(bucketdir)) class Stats(unittest.TestCase):