From cd69bf51ca11a102a13ba30c2800ff4d553996bf Mon Sep 17 00:00:00 2001
From: Maxim Dounin <mdounin@mdounin.ru>
Date: Mon, 22 Jun 2020 18:02:58 +0300
Subject: Large block sizes on Linux are now ignored (ticket #1168).

NFS on Linux is known to report wsize as a block size (in both f_bsize
and f_frsize, both in statfs() and statvfs()).  On the other hand,
typical file system block sizes on Linux (ext2/ext3/ext4, XFS) are limited
to pagesize.  (With FAT, block sizes can be at least up to 512k in
extreme cases, but this doesn't really matter, see below.)
To avoid too aggressive cache clearing on NFS volumes on Linux, block
sizes larger than pagesize are now ignored.

Note that it is safe to ignore large block sizes.  Since 3899:e7cd13b7f759
(1.0.1) cache size is calculated based on fstat() st_blocks, and rounding
to file system block size is preserved mostly for Windows.

Note well that on other OSes valid block sizes seen are at least up
to 65536.  In particular, UFS on FreeBSD is known to work well with block
and fragment sizes set to 65536.
---
 src/os/unix/ngx_files.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

(limited to 'src/os/unix/ngx_files.c')

diff --git a/src/os/unix/ngx_files.c b/src/os/unix/ngx_files.c
index 482d32763..7e8e58fe7 100644
--- a/src/os/unix/ngx_files.c
+++ b/src/os/unix/ngx_files.c
@@ -875,6 +875,12 @@ ngx_fs_bsize(u_char *name)
         return 512;
     }
 
+#if (NGX_LINUX)
+    if ((size_t) fs.f_bsize > ngx_pagesize) {
+        return 512;
+    }
+#endif
+
     return (size_t) fs.f_bsize;
 }
 
@@ -893,6 +899,12 @@ ngx_fs_bsize(u_char *name)
         return 512;
     }
 
+#if (NGX_LINUX)
+    if ((size_t) fs.f_frsize > ngx_pagesize) {
+        return 512;
+    }
+#endif
+
     return (size_t) fs.f_frsize;
 }
 
-- 
cgit v1.2.3


From 0a683fdd9313b9796bf39442fd117beaa63a7157 Mon Sep 17 00:00:00 2001
From: Maxim Dounin <mdounin@mdounin.ru>
Date: Mon, 22 Jun 2020 18:03:00 +0300
Subject: Cache: introduced min_free cache clearing.

Clearing cache based on free space left on a file system is
expected to allow better disk utilization in some cases, notably
when disk space might be also used for something other than nginx
cache (including nginx own temporary files) and while loading
cache (when cache size might be inaccurate for a while, effectively
disabling max_size cache clearing).

Based on a patch by Adam Bambuch.
---
 src/os/unix/ngx_files.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

(limited to 'src/os/unix/ngx_files.c')

diff --git a/src/os/unix/ngx_files.c b/src/os/unix/ngx_files.c
index 7e8e58fe7..1c82a8ead 100644
--- a/src/os/unix/ngx_files.c
+++ b/src/os/unix/ngx_files.c
@@ -884,6 +884,19 @@ ngx_fs_bsize(u_char *name)
     return (size_t) fs.f_bsize;
 }
 
+
+off_t
+ngx_fs_available(u_char *name)
+{
+    struct statfs  fs;
+
+    if (statfs((char *) name, &fs) == -1) {
+        return NGX_MAX_OFF_T_VALUE;
+    }
+
+    return (off_t) fs.f_bavail * fs.f_bsize;
+}
+
 #elif (NGX_HAVE_STATVFS)
 
 size_t
@@ -908,6 +921,19 @@ ngx_fs_bsize(u_char *name)
     return (size_t) fs.f_frsize;
 }
 
+
+off_t
+ngx_fs_available(u_char *name)
+{
+    struct statvfs  fs;
+
+    if (statvfs((char *) name, &fs) == -1) {
+        return NGX_MAX_OFF_T_VALUE;
+    }
+
+    return (off_t) fs.f_bavail * fs.f_frsize;
+}
+
 #else
 
 size_t
@@ -916,4 +942,11 @@ ngx_fs_bsize(u_char *name)
     return 512;
 }
 
+
+off_t
+ngx_fs_available(u_char *name)
+{
+    return NGX_MAX_OFF_T_VALUE;
+}
+
 #endif
-- 
cgit v1.2.3