.

bigfile/file_zodb.py

@@ -81,7 +81,7 @@ natural to also use "2" here.
 # FIXME ^^^ doc is horrible - add top-level up->down overview.
 
 from wendelin.bigfile import BigFile, WRITEOUT_STORE, WRITEOUT_MARKSTORED
-from wendelin import wcfs   # XXX -> wendelin.bigfile.wcfs ?
+from wendelin import wcfs
 from wendelin.lib.mem import bzero, memcpy
 from wendelin.lib.zodb import deactivate_btree
 

wcfs/__init__.py

@@ -96,6 +96,7 @@ class Conn(object):
 class _File(object):
     # .wconn    Conn
     # .foid     hex of ZBigFile root object ID
+    # .blksize  block size of this file
     # .headf    file object of head/file
     # .pinned   {} blk -> rev   that wcfs already sent us for this file
     # .mmaps    []_Mapping ↑blk_start    mappings of this file
@@ -169,7 +170,7 @@ def _pinner(wconn, ctx):
 
 # mmap creates file mapping representing file data as of wconn.at database state.
 @func(Conn)
-def mmap(wconn, foid, offset, size): # -> Mapping       XXX offset, size -> blkoff, blksize ?
+def mmap(wconn, foid, blk, blklen): # -> Mapping
     with wconn._filemu:
         f = wconn._filetab.get(foid)
         if f is None:
@@ -177,6 +178,7 @@ def mmap(wconn, foid, offset, size): # -> Mapping       XXX offset, size -> blko
             f.wconn     = wconn
             f.foid      = foid
             f.headf     = wconn._wc._open("head/bigfile/%s" % (ashex(foid),), "rb")
+            f.blksize   = os.fstat(f.headf.fileno()).st_blksize
             f.pinned    = {}
             f.mmaps     = []
             wconn._filetab[foid] = f
@@ -184,7 +186,7 @@ def mmap(wconn, foid, offset, size): # -> Mapping       XXX offset, size -> blko
         # XXX relock wconn -> f ?
 
         # create memory with head/f mapping and applied pins
-        mem = mm.map_ro(f.headf.fileno(), offset, size)
+        mem = mm.map_ro(f.headf.fileno(), blk*f.blksize, blklen*f.blksize)
         mmap = _Mapping(f, blk_start, mem)
         for blk, rev in f.pinned.items():  # XXX keep f.pinned ↑blk and use binary search?
             if not (blk_start <= blk < blk_stop):
@@ -210,6 +212,7 @@ def _remmapblk(mmap, blk, at):
         # TODO share @rev fd until wconn is resynced?
         fsfile = f.wconn._wc._open("@%s/bigfile/%s" % (ashex(at), ashex(f.foid)), "rb")
         defer(fsfile.close)
+        assert os.fstat(fsfile.fileno()).st_blksize == f.blksize  # FIXME assert
 
     mm.map_into_ro(mmap.mem[(blk-mmap.blk_start)*blksize:][:blksize], fsfile.fileno(), blk*blksize)
 

wcfs/wcfs.go

@@ -2190,8 +2190,8 @@ func (f *BigFile) GetAttr(out *fuse.Attr, _ nodefs.File, _ *fuse.Context) fuse.S
 func (f *BigFile) getattr(out *fuse.Attr) {
 	out.Mode = fuse.S_IFREG | 0444
 	out.Size = uint64(f.size)
+	out.Blksize = uint32(f.blksize)	// XXX 64 -> 32
 	// .Blocks
-	// .Blksize
 
 	mtime := f.rev.Time().Time
 	out.SetTimes(/*atime=*/nil, /*mtime=*/&mtime, /*ctime=*/&mtime)

wcfs/wcfs_test.py

@@ -1074,6 +1074,10 @@ def test_wcfs_basic():
         t.wc._stat("head/bigfile/%s" % h(t.nonzfile._p_oid))
     assert exc.value.errno == EINVAL
 
+    # make sure that wcfs reports zf.blksize as preffered block size for IO
+    _ = t.wc._stat(zf)
+    assert _.st_blksize == zf.blksize
+
     # >>> file initially empty
     f = t.open(zf)
     f.assertCache([])