From 3b2a68fe7afb586b8797fc63d40e271794fc2bc6 Mon Sep 17 00:00:00 2001
From: MattJackson <1085847+MattJackson@users.noreply.github.com>
Date: Sat, 16 May 2026 09:30:44 -0700
Subject: [PATCH] =?UTF-8?q?Revert=20"io/pipeline:=20bump=20WRITE=5FPIPELIN?=
 =?UTF-8?q?E=5FDEPTH=2016=20=E2=86=92=2032"?=
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This reverts commit d703ce439bc4d1141bf711f71aafddff98c963d4.
---
 src/io/pipeline.rs | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/src/io/pipeline.rs b/src/io/pipeline.rs
index 0c4baba..eb9d47f 100644
--- a/src/io/pipeline.rs
+++ b/src/io/pipeline.rs
@@ -92,16 +92,10 @@ pub const DEFAULT_PIPELINE_DEPTH: usize = 4;
 /// consumer blocks on write.
 pub const READ_PIPELINE_DEPTH: usize = 32;
 
-/// Write pipeline depth. 0.21.8 restored the writer-thread + 128 MiB
-/// byte-bounded ring inside WritebackFile, which absorbs kernel
-/// writeback stalls downstream of this channel. The pre-0.21.8
-/// rationale ("smaller buffer reduces backpressure risk when
-/// sync_file_range blocks") no longer applies — `sync_file_range` only
-/// hits the writer thread, never this channel. Doubling 16 → 32 gives
-/// the matroska builder headroom to keep emitting frames when the sink
-/// momentarily lags behind, smoothing out the 5-50 MB/s instantaneous
-/// burst pattern observed on NFS bidirectional workloads at 0.21.8.
-pub const WRITE_PIPELINE_DEPTH: usize = 32;
+/// Write pipeline depth. Smaller buffer reduces backpressure risk when
+/// sync_file_range blocks; prevents producer from accumulating too much
+/// work while consumer waits for NFS to drain.
+pub const WRITE_PIPELINE_DEPTH: usize = 16;
 
 /// Channel depth for write-through pipelines. Each `send` fully
 /// drains before the next can enqueue. Use this when the producer