From 5929bf57cca6f17c528bfe215f8bec0e55d65398 Mon Sep 17 00:00:00 2001
From: Yorhel <git@yorhel.nl>
Date: Wed, 28 Jul 2021 20:12:50 +0200
Subject: [PATCH] Keep track of uncounted hard links to speed up refresh+delete
operations
---
src/model.zig | 34 +++++++++++++++++++++++++++++-----
1 file changed, 29 insertions(+), 5 deletions(-)
diff --git a/src/model.zig b/src/model.zig
index 43e20a6..42f2a78 100644
--- a/src/model.zig
+++ b/src/model.zig
@@ -134,7 +134,7 @@ pub const Entry = packed struct {
l.next = d.key_ptr.*.next;
d.key_ptr.*.next = l;
}
-
+ inodes.addUncounted(l);
}
var it: ?*Dir = parent;
@@ -173,10 +173,12 @@ pub const Entry = packed struct {
d.value_ptr.nlink = 0;
if (l.next == l) {
_ = inodes.map.remove(l);
+ _ = inodes.uncounted.remove(l);
inodes.total_blocks = saturateSub(inodes.total_blocks, self.blocks);
} else {
if (d.key_ptr.* == l)
d.key_ptr.* = l.next;
+ inodes.addUncounted(l.next);
// This is O(n), which in this context has the potential to
// slow ncdu down to a crawl. But this function is only called
// on refresh/delete operations and even then it's not common
@@ -343,6 +345,13 @@ pub const inodes = struct {
// the hard links are not counted as part of the parent directories yet.
pub var total_blocks: Blocks = 0;
+ // List of nodes in 'map' with !counted, to speed up addAllStats().
+ // If this list grows large relative to the number of nodes in 'map', then
+ // this list is cleared and uncounted_full is set instead, so that
+ // addAllStats() will do a full iteration over 'map'.
+ var uncounted = std.HashMap(*Link, void, HashContext, 80).init(main.allocator);
+ var uncounted_full = true; // start with true for the initial scan
+
const Inode = packed struct {
// Whether this Inode is counted towards the parent directories.
counted: bool,
@@ -367,6 +376,15 @@ pub const inodes = struct {
}
};
+ fn addUncounted(l: *Link) void {
+ if (uncounted_full) return;
+ if (uncounted.count() > map.count()/8) {
+ uncounted.clearAndFree();
+ uncounted_full = true;
+ } else
+ (uncounted.getOrPut(l) catch unreachable).key_ptr.* = l;
+ }
+
// Add/remove this inode from the parent Dir sizes. When removing stats,
// the list of *Links and their sizes and counts must be in the exact same
// state as when the stats were added. Hence, any modification to the Link
@@ -419,11 +437,17 @@ pub const inodes = struct {
}
}
- // TODO: A version that doesn't have to iterate over the entire map, for
- // smaller refresh/delete updates.
pub fn addAllStats() void {
- var it = map.iterator();
- while (it.next()) |e| setStats(e, true);
+ if (uncounted_full) {
+ var it = map.iterator();
+ while (it.next()) |e| setStats(e, true);
+ } else {
+ var it = uncounted.iterator();
+ while (it.next()) |u| if (map.getEntry(u.key_ptr.*)) |e| setStats(e, true);
+ }
+ uncounted_full = false;
+ if (uncounted.count() > 0)
+ uncounted.clearAndFree();
}
};
--
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