From db3b2316f0578f87da66938d88b66777ca90760a Mon Sep 17 00:00:00 2001
From: Puck Meerburg <puck@puckipedia.com>
Date: Sun, 11 May 2025 22:21:07 +0000
Subject: [PATCH] (zilch magic): configurable CA build job count

Change-Id: I6a6a6964f157a33b35dae7245c344be7907c5221
---
 cli/zilch-ninja.scm | 14 ++++++++------
 core/src/magic.sld  |  6 ++++--
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/cli/zilch-ninja.scm b/cli/zilch-ninja.scm
index 79730fd..f425c34 100644
--- a/cli/zilch-ninja.scm
+++ b/cli/zilch-ninja.scm
@@ -38,12 +38,12 @@ to final build, or to specific Ninja targets.
 ; Set up the logger.
 (define (set-print-logs val) #f)
 (let ((prev-error-handler (current-exception-handler))) (current-exception-handler (lambda data (set-print-logs #t) (apply prev-error-handler data))))
-(when (terminal-port? (current-error-port))
- (let-values (((new-out new-err statusbar-set-print-logs logger) (statusbar-logger (current-output-port) (current-error-port) (assoc 'print-build-logs options))))
-   (current-output-port new-out)
-   (current-error-port new-err)
-   (set! set-print-logs statusbar-set-print-logs)
-   (*logger* logger)))
+; (when (terminal-port? (current-error-port))
+;  (let-values (((new-out new-err statusbar-set-print-logs logger) (statusbar-logger (current-output-port) (current-error-port) (assoc 'print-build-logs options))))
+;    (current-output-port new-out)
+;    (current-error-port new-err)
+;    (set! set-print-logs statusbar-set-print-logs)
+;    (*logger* logger)))
 
 ;; Flags passed to the nix daemon:
 (define max-jobs (if (assoc 'max-jobs options) (string->number (cdr (assoc 'max-jobs options))) (get-cpu-count)))
@@ -52,6 +52,8 @@ to final build, or to specific Ninja targets.
 (write-string (string-append "Connected to Nix daemon, version " (daemon-link-daemon-version (*daemon*)) "\n") (current-error-port))
 
 (daemon-wop-set-options (*daemon*) verbosity max-jobs #t)
+(ca-thread-count max-jobs)
+
 (import
   (scheme base) (scheme file) (scheme read)
   (chicken format)
diff --git a/core/src/magic.sld b/core/src/magic.sld
index 30e995d..6c22fc4 100644
--- a/core/src/magic.sld
+++ b/core/src/magic.sld
@@ -23,7 +23,7 @@
     store-path-realised store-path-open
     store-path-devirtualise
 
-    drv-resolve-ca
+    ca-thread-count drv-resolve-ca
 
     zilch-magic-counters)
 
@@ -333,6 +333,8 @@
    (define-record-printer (<pending-item> item out)
     (fprintf out "#<pending-item ~A - awaiting ~S>" (derivation-path (pending-item-ca-drv item)) (pending-item-awaiting-count item)))
 
+   (define ca-thread-count (make-parameter 4))
+
    (define (rewrite-ca-stack input-drv)
      ; A mapping of CA derivation path to <pending-item>.
      (define ca-to-pending-map (mapping (make-default-comparator)))
@@ -478,7 +480,7 @@
               (builder quit conn))))))
 
      (define builder-threads '())
-     (do ((i 0 (+ i 1))) ((>= i 16) #f)
+     (do ((i 0 (+ i 1))) ((>= i (ca-thread-count)) #f)
        (set! builder-threads
         (cons
          (thread-start!