Merge pull request trapexit#815 from trapexit/policy-pfrd

add {,ep,msp}pfrd policies
kodavn · Aug 26, 2020 · 3534fb1 · 3534fb1
2 parents 7ff9956 + 0468440
commit 3534fb1
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diff --git a/README.md b/README.md
@@ -1,6 +1,6 @@
 % mergerfs(1) mergerfs user manual
 % Antonio SJ Musumeci <trapexit@spawn.link>
-% 2020-08-07
+% 2020-08-20
 
 # NAME
 
@@ -306,22 +306,25 @@ Because of the nature of the behavior the policies act diffierently depending on
 
 | Policy           | Description                                                |
 |------------------|------------------------------------------------------------|
-| all | Search: same as **epall**. Action: same as **epall**. Create: for **mkdir**, **mknod**, and **symlink** it will apply to all branches. **create** works like **ff**. |
-| epall (existing path, all) | Search: same as **epff** (but more expensive because it doesn't stop after finding a valid branch). Action: apply to all found. Create: for **mkdir**, **mknod**, and **symlink** it will apply to all found. **create** works like **epff** (but more expensive because it doesn't stop after finding a valid branch). |
+| all | Search: Same as **epall**. Action: Same as **epall**. Create: for **mkdir**, **mknod**, and **symlink** it will apply to all branches. **create** works like **ff**. |
+| epall (existing path, all) | Search: Same as **epff** (but more expensive because it doesn't stop after finding a valid branch). Action: apply to all found. Create: for **mkdir**, **mknod**, and **symlink** it will apply to all found. **create** works like **epff** (but more expensive because it doesn't stop after finding a valid branch). |
 | epff (existing path, first found) | Given the order of the branches, as defined at mount time or configured at runtime, act on the first one found where the relative path exists. |
 | eplfs (existing path, least free space) | Of all the branches on which the relative path exists choose the drive with the least free space. |
 | eplus (existing path, least used space) | Of all the branches on which the relative path exists choose the drive with the least used space. |
 | epmfs (existing path, most free space) | Of all the branches on which the relative path exists choose the drive with the most free space. |
+| eppfrd (existing path, percentage free random distribution) | Like **pfrd** but limited to existing paths.  |
 | eprand (existing path, random) | Calls **epall** and then randomizes. Returns 1. |
 | erofs | Exclusively return **-1** with **errno** set to **EROFS** (read-only filesystem). |
-| ff (first found) | Search: same as **epff**. Action: same as **epff**. Create: Given the order of the drives, as defined at mount time or configured at runtime, act on the first one found. |
-| lfs (least free space) | Search: same as **eplfs**. Action: same as **eplfs**. Create: Pick the drive with the least available free space. |
-| lus (least used space) | Search: same as **eplus**. Action: same as **eplus**. Create: Pick the drive with the least used space. |
-| mfs (most free space) | Search: same as **epmfs**. Action: same as **epmfs**. Create: Pick the drive with the most available free space. |
-| msplfs (most shared path, least free space) | Search: same as **eplfs**. Action: same as **eplfs**. Create: like **eplfs** but walk back the path if it fails to find a branch at that level. |
-| msplus (most shared path, least used space) | Search: same as **eplus**. Action: same as **eplus**. Create: like **eplus** but walk back the path if it fails to find a branch at that level. |
-| mspmfs (most shared path, most free space) | Search: same as **epmfss**. Action: same as **epmfs**. Create: like **eplmfs** but walk back the path if it fails to find a branch at that level. |
+| ff (first found) | Search: Same as **epff**. Action: Same as **epff**. Create: Given the order of the drives, as defined at mount time or configured at runtime, act on the first one found. |
+| lfs (least free space) | Search: Same as **eplfs**. Action: Same as **eplfs**. Create: Pick the drive with the least available free space. |
+| lus (least used space) | Search: Same as **eplus**. Action: Same as **eplus**. Create: Pick the drive with the least used space. |
+| mfs (most free space) | Search: Same as **epmfs**. Action: Same as **epmfs**. Create: Pick the drive with the most available free space. |
+| msplfs (most shared path, least free space) | Search: Same as **eplfs**. Action: Same as **eplfs**. Create: like **eplfs** but walk back the path if it fails to find a branch at that level. |
+| msplus (most shared path, least used space) | Search: Same as **eplus**. Action: Same as **eplus**. Create: like **eplus** but walk back the path if it fails to find a branch at that level. |
+| mspmfs (most shared path, most free space) | Search: Same as **epmfss**. Action: Same as **epmfs**. Create: like **eplmfs** but walk back the path if it fails to find a branch at that level. |
+| msppfrd (most shared path, percentage free random distribution) | Search: Same as **eppfrd**. Action: Same as **eppfrd**. Create: Like **eppfrd** but will walk back the path if it fails to find a branch at that level. |
 | newest | Pick the file / directory with the largest mtime. |
+| pfrd (percentage free random distribution) | Search: Same as **eppfrd**. Action: Same as **eppfrd**. Create: Chooses a branch at random with the likelihood of selection based on a branch's available space relative to the total. |
 | rand (random) | Calls **all** and then randomizes. Returns 1. |
 
 **NOTE:** If you are using an underlying filesystem that reserves blocks such as ext2, ext3, or ext4 be aware that mergerfs respects the reservation by using `f_bavail` (number of free blocks for unprivileged users) rather than `f_bfree` (number of free blocks) in policy calculations. **df** does NOT use `f_bavail`, it uses `f_bfree`, so direct comparisons between **df** output and mergerfs' policies is not appropriate.

diff --git a/man/mergerfs.1 b/man/mergerfs.1
@@ -1,7 +1,7 @@
 .\"t
 .\" Automatically generated by Pandoc 1.19.2.4
 .\"
-.TH "mergerfs" "1" "2020\-08\-07" "mergerfs user manual" ""
+.TH "mergerfs" "1" "2020\-08\-20" "mergerfs user manual" ""
 .hy
 .SH NAME
 .PP
@@ -778,6 +778,11 @@ Of all the branches on which the relative path exists choose the drive
 with the most free space.
 T}
 T{
+eppfrd (existing path, percentage free random distribution)
+T}@T{
+Like \f[B]pfrd\f[] but limited to existing paths.
+T}
+T{
 eprand (existing path, random)
 T}@T{
 Calls \f[B]epall\f[] and then randomizes.
@@ -843,11 +848,27 @@ Create: like \f[B]eplmfs\f[] but walk back the path if it fails to find
 a branch at that level.
 T}
 T{
+msppfrd (most shared path, percentage free random distribution)
+T}@T{
+Search: same as \f[B]eppfrd\f[].
+Action: same as \f[B]eppfrd\f[].
+Create: Like \f[B]eppfrd\f[] but will walk back the path if it fails to
+find a branch at that level.
+T}
+T{
 newest
 T}@T{
 Pick the file / directory with the largest mtime.
 T}
 T{
+pfrd (percentage free random distribution)
+T}@T{
+Search: same as \f[B]eppfrd\f[].
+Action: same as \f[B]eppfrd\f[].
+Create: Chooses a branch at random with the likelihood of selection
+based on a branch\[aq]s available space relative to the total.
+T}
+T{
 rand (random)
 T}@T{
 Calls \f[B]all\f[] and then randomizes.

diff --git a/src/policy.cpp b/src/policy.cpp
@@ -32,6 +32,7 @@ const std::vector<Policy> Policy::_policies_ =
   (POLICY(eplfs,PRESERVES_PATH))
   (POLICY(eplus,PRESERVES_PATH))
   (POLICY(epmfs,PRESERVES_PATH))
+  (POLICY(eppfrd,PRESERVES_PATH))
   (POLICY(eprand,PRESERVES_PATH))
   (POLICY(erofs,DOESNT_PRESERVE_PATH))
   (POLICY(ff,DOESNT_PRESERVE_PATH))
@@ -41,7 +42,9 @@ const std::vector<Policy> Policy::_policies_ =
   (POLICY(msplfs,PRESERVES_PATH))
   (POLICY(msplus,PRESERVES_PATH))
   (POLICY(mspmfs,PRESERVES_PATH))
+  (POLICY(msppfrd,PRESERVES_PATH))
   (POLICY(newest,DOESNT_PRESERVE_PATH))
+  (POLICY(pfrd,DOESNT_PRESERVE_PATH))
   (POLICY(rand,DOESNT_PRESERVE_PATH));
 
 const Policy * const Policy::policies = &_policies_[1];
@@ -55,6 +58,7 @@ CONST_POLICY(epff);
 CONST_POLICY(eplfs);
 CONST_POLICY(eplus);
 CONST_POLICY(epmfs);
+CONST_POLICY(eppfrd);
 CONST_POLICY(eprand);
 CONST_POLICY(erofs);
 CONST_POLICY(ff);
@@ -64,19 +68,21 @@ CONST_POLICY(mfs);
 CONST_POLICY(msplfs);
 CONST_POLICY(msplus);
 CONST_POLICY(mspmfs);
+CONST_POLICY(msppfrd);
 CONST_POLICY(newest);
+CONST_POLICY(pfrd);
 CONST_POLICY(rand);
 
 const Policy&
 Policy::find(const std::string &str)
 {
-for(int i = Enum::BEGIN; i != Enum::END; ++i)
-  {
-    if(policies[i] == str)
-      return policies[i];
-  }
+  for(int i = Enum::BEGIN; i != Enum::END; ++i)
+    {
+      if(policies[i] == str)
+        return policies[i];
+    }
 
- return invalid;
+  return invalid;
 }
 
 const Policy&

diff --git a/src/policy.hpp b/src/policy.hpp
@@ -37,6 +37,7 @@ class Policy
         eplfs,
         eplus,
         epmfs,
+        eppfrd,
         eprand,
         erofs,
         ff,
@@ -46,7 +47,9 @@ class Policy
         msplfs,
         msplus,
         mspmfs,
+        msppfrd,
         newest,
+        pfrd,
         rand,
         END
       };
@@ -117,6 +120,7 @@ class Policy
     static int eplfs(Category,const Branches&,const char *,cuint64_t,strvec*);
     static int eplus(Category,const Branches&,const char *,cuint64_t,strvec*);
     static int epmfs(Category,const Branches&,const char *,cuint64_t,strvec*);
+    static int eppfrd(Category,const Branches&,const char *,cuint64_t,strvec*);
     static int eprand(Category,const Branches&,const char *,cuint64_t,strvec*);
     static int erofs(Category,const Branches&,const char *,cuint64_t,strvec*);
     static int ff(Category,const Branches&,const char *,cuint64_t,strvec*);
@@ -126,7 +130,9 @@ class Policy
     static int msplfs(Category,const Branches&,const char *,cuint64_t,strvec*);
     static int msplus(Category,const Branches&,const char *,cuint64_t,strvec*);
     static int mspmfs(Category,const Branches&,const char *,cuint64_t,strvec*);
+    static int msppfrd(Category,const Branches&,const char *,cuint64_t,strvec*);
     static int newest(Category,const Branches&,const char *,cuint64_t,strvec*);
+    static int pfrd(Category,const Branches&,const char *,cuint64_t,strvec*);
     static int rand(Category,const Branches&,const char *,cuint64_t,strvec*);
   };
 
@@ -198,6 +204,7 @@ class Policy
   static const Policy &eplfs;
   static const Policy &eplus;
   static const Policy &epmfs;
+  static const Policy &eppfrd;
   static const Policy &eprand;
   static const Policy &erofs;
   static const Policy &ff;
@@ -207,7 +214,9 @@ class Policy
   static const Policy &msplfs;
   static const Policy &msplus;
   static const Policy &mspmfs;
+  static const Policy &msppfrd;
   static const Policy &newest;
+  static const Policy &pfrd;
   static const Policy &rand;
 };