fellow_tune: Remove objsize_hint tunable

The potential impact of changing this parameter to a wrong value is too
high, so we better rely on changes to automatically adjust it (coming
up).

Ref #54

src/fellow_tune.h

@@ -32,8 +32,10 @@ struct stvfe_tune {
 	t	n
 #include "tbl/fellow_tunables.h"
 
-	size_t			memsz;
+	// constructor arguments
 	size_t			dsksz;
+	size_t			memsz;
+	size_t			objsize_hint;
 };
 
 const char * stvfe_tune_init(struct stvfe_tune *tune,

src/tbl/fellow_tunables.h

@@ -45,7 +45,6 @@ TUNE(uint8_t, wait_table_exponent, 10, 6, 32);
 TUNE(uint8_t, lru_exponent, 0, 0, 6);
 TUNE(unsigned, dsk_reserve_chunks, 4, 2, UINT_MAX);
 TUNE(unsigned, mem_reserve_chunks, 1, 0, UINT_MAX);
-TUNE(size_t, objsize_hint, 256 * 1024, 4096, SIZE_MAX);
 TUNE(size_t, objsize_max, 0, 0, SIZE_MAX);
 TUNE(size_t, discard_immediate, 256 * 1024, 4096, SIZE_MAX);
 // 31 is safe max for stack usage, further limited by memsz

src/vmod_slash.man.rst

@@ -51,7 +51,7 @@ vcl storage objects and methods
 
   new xfellow = slash.fellow(STRING filename, BYTES dsksize, BYTES memsize, BYTES objsize_hint, BOOL delete)
 
-      STRING xfellow.tune([INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_hint], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
+      STRING xfellow.tune([INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
 
       STEVEDORE xfellow.storage()
 
@@ -68,7 +68,7 @@ vcl functions
 
   STRING tune_buddy(STEVEDORE storage, [INT chunk_exponent], [BYTES chunk_bytes], [INT reserve_chunks], [INT cram])
 
-  STRING tune_fellow(STEVEDORE storage, [INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_hint], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
+  STRING tune_fellow(STEVEDORE storage, [INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
 
 vcl loadmasters (storage routers)
 ---------------------------------
@@ -237,9 +237,9 @@ argument.
 Memory Cache Sharing
 ~~~~~~~~~~~~~~~~~~~~
 
-When memory cache sharing with the ``<memsize>[=<storage>]``
-syntax is configured, *<memsize>* is used for sanity checking
-only. The actual memory size is always that of the referenced storage.
+When memory cache sharing with the ``<memsize>[=<storage>]`` syntax is
+configured, *<memsize>* is ignored. The actual memory size is always
+that of the referenced storage.
 
 LRU with memory cache sharing is cooperative. Whenever memory is
 needed by any storage, all storages using the shared cache are asked
@@ -473,10 +473,16 @@ actual figures are output at startup as ``fellow: metadata (bitmap)
 memory``.
 
 *objsize_hint* (default 256KB) is used to sanity check *memsize* in
-relation to *dsksize*. It should be set to a value lower than the
-average object size (actual or expected). If *memsize* is configured
-too low with respect to *dsksize* and *objsize_hint*, a higher value
-will be used (which might fail of insufficient memory is available).
+relation to *dsksize* and to size the fixed log regions. It should be
+set to a value **lower** than the expected average object size. If
+*memsize* is configured too low with respect to *dsksize* and
+*objsize_hint*, a higher *memsize* value will be used (which might
+fail if insufficient memory is available).
+
+For an already populated storage, the configured *memsize* is checked
+against the minimum amount of memory required for the actual average
+object size. If it is too low, fellow will not start and emit a fatal
+error with sizing requirements.
 
 *delete* specifies if the storage is to be emptied.
 
@@ -571,8 +577,8 @@ Decreasing ``dsksize``
 
 .. _xfellow.tune():
 
-STRING xfellow.tune([INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT wait_table_exponent], [INT lru_exponent], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_hint], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+STRING xfellow.tune([INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT wait_table_exponent], [INT lru_exponent], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 
 ::
 
@@ -586,7 +592,6 @@ STRING xfellow.tune([INT logbuffer_size], [DURATION logbuffer_flush_interval], [
             [INT lru_exponent],
             [INT dsk_reserve_chunks],
             [INT mem_reserve_chunks],
-            [BYTES objsize_hint],
             [BYTES objsize_max],
             [INT cram],
             [INT readahead],
@@ -735,16 +740,6 @@ fellow storage can be fine tuned:
   The value is capped suck that the number of reserved chunks times
   the chunk size does not exceed 1/8 of the memory size.
 
-* *objsize_hint*
-
-  - unit: bytes
-  - default: 256KB
-  - minimum: 4KB
-
-  specifies an estimate of the average object size in cache. It is
-  used to (re)size the fixed log space. The value should be chosen as
-  a safe *lower* bound of average object size.
-
 * *objsize_max*
 
   - unit: bytes
@@ -953,8 +948,8 @@ Restricted to: ``vcl_init``.
 
 .. _slash.tune_fellow():
 
-STRING tune_fellow(STEVEDORE storage, [INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT wait_table_exponent], [INT lru_exponent], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_hint], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+STRING tune_fellow(STEVEDORE storage, [INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT wait_table_exponent], [INT lru_exponent], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 
 ::
 
@@ -969,7 +964,6 @@ STRING tune_fellow(STEVEDORE storage, [INT logbuffer_size], [DURATION logbuffer_
       [INT lru_exponent],
       [INT dsk_reserve_chunks],
       [INT mem_reserve_chunks],
-      [BYTES objsize_hint],
       [BYTES objsize_max],
       [INT cram],
       [INT readahead],

src/vmod_slash.vcc

@@ -36,7 +36,7 @@ vcl storage objects and methods
 
   new xfellow = slash.fellow(STRING filename, BYTES dsksize, BYTES memsize, BYTES objsize_hint, BOOL delete)
 
-      STRING xfellow.tune([INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_hint], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
+      STRING xfellow.tune([INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
 
       STEVEDORE xfellow.storage()
 
@@ -53,7 +53,7 @@ vcl functions
 
   STRING tune_buddy(STEVEDORE storage, [INT chunk_exponent], [BYTES chunk_bytes], [INT reserve_chunks], [INT cram])
 
-  STRING tune_fellow(STEVEDORE storage, [INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_hint], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
+  STRING tune_fellow(STEVEDORE storage, [INT logbuffer_size], [DURATION logbuffer_flush_interval], [REAL log_rewrite_ratio], [INT chunk_exponent], [BYTES chunk_bytes], [INT dsk_reserve_chunks], [INT mem_reserve_chunks], [BYTES objsize_max], [INT cram], [INT readahead], [BYTES discard_immediate], [INT io_batch_min], [INT io_batch_max], [ENUM hash_obj], [ENUM hash_log], [ENUM ioerr_obj], [ENUM ioerr_log], [ENUM allocerr_obj], [ENUM allocerr_log])
 
 vcl loadmasters (storage routers)
 ---------------------------------
@@ -525,13 +525,13 @@ $Method STRING .tune( [ INT logbuffer_size ], [ DURATION
 	chunk_exponent ], [ BYTES chunk_bytes ], [ INT
 	wait_table_exponent ], [ INT lru_exponent ], [ INT
 	dsk_reserve_chunks ], [ INT mem_reserve_chunks ], [ BYTES
-	objsize_hint ], [ BYTES objsize_max ], [ INT cram ], [ INT
-	readahead ], [ BYTES discard_immediate ], [ INT io_batch_min
-	], [ INT io_batch_max ], [ ENUM { sha256, xxh32, xxh3_64,
-	xxh3_128 } hash_obj ], [ ENUM { sha256, xxh32, xxh3_64,
-	xxh3_128 } hash_log ], [ ENUM { panic, purge } ioerr_obj ], [
-	ENUM { panic, fail } ioerr_log ], [ ENUM { panic, purge }
-	allocerr_obj ], [ ENUM { panic, fail } allocerr_log ])
+	objsize_max ], [ INT cram ], [ INT readahead ], [ BYTES
+	discard_immediate ], [ INT io_batch_min ], [ INT io_batch_max
+	], [ ENUM { sha256, xxh32, xxh3_64, xxh3_128 } hash_obj ], [
+	ENUM { sha256, xxh32, xxh3_64, xxh3_128 } hash_log ], [ ENUM {
+	panic, purge } ioerr_obj ], [ ENUM { panic, fail } ioerr_log
+	], [ ENUM { panic, purge } allocerr_obj ], [ ENUM { panic,
+	fail } allocerr_log ])
 
 Using the `xfellow.tune()`_ method, the following parameters of the
 fellow storage can be fine tuned:
@@ -667,16 +667,6 @@ fellow storage can be fine tuned:
   The value is capped suck that the number of reserved chunks times
   the chunk size does not exceed 1/8 of the memory size.
 
-* *objsize_hint*
-
-  - unit: bytes
-  - default: 256KB
-  - minimum: 4KB
-
-  specifies an estimate of the average object size in cache. It is
-  used to (re)size the fixed log space. The value should be chosen as
-  a safe *lower* bound of average object size.
-
 * *objsize_max*
 
   - unit: bytes
@@ -881,7 +871,6 @@ $Function STRING tune_fellow(
 	[ INT		lru_exponent ],
 	[ INT		dsk_reserve_chunks ],
 	[ INT		mem_reserve_chunks ],
-	[ BYTES		objsize_hint ],
 	[ BYTES		objsize_max ],
 	[ INT		cram ],
 	[ INT		readahead ],

src/vtc/fellow_global.vtc

@@ -38,10 +38,6 @@ varnish v1 \
 			set resp.http.e = slash.tune_fellow(storage.fellow, mem_reserve_chunks =
 				std.integer(req.http.mem-reserve-chunks));
 		}
-		else if (req.http.objsize-hint) {
-			set resp.http.e = slash.tune_fellow(storage.fellow, objsize_hint =
-				std.bytes(req.http.objsize-hint));
-		}
 		else {
 			set resp.http.e = "Unknown tunable header";
 		}
@@ -243,24 +239,12 @@ client c6 -repeat 1 {
 	expect resp.body == "Value of mem_reserve_chunks must not be negative"
 } -start
 
-client c7 -repeat 1 {
-	txreq -url "/tune" -hdr "objsize-hint: 1MB"
-	rxresp
-	expect resp.status == 200
-	expect resp.body == ""
-	txreq -url "/tune" -hdr "objsize-hint: 1KB"
-	rxresp
-	expect resp.status == 400
-	expect resp.body == "Value of objsize_hint is too small, minimum is 4096"
-} -start
-
 client c1 -wait
 client c2 -wait
 client c3 -wait
 client c4 -wait
 client c5 -wait
 client c6 -wait
-client c7 -wait
 
 varnish v1 -vcl {
 	backend none none;

src/vtc/fellow_global_shared.vtc

@@ -39,10 +39,6 @@ varnish v1 \
 			set resp.http.e = slash.tune_fellow(storage.fellow, mem_reserve_chunks =
 				std.integer(req.http.mem-reserve-chunks));
 		}
-		else if (req.http.objsize-hint) {
-			set resp.http.e = slash.tune_fellow(storage.fellow, objsize_hint =
-				std.bytes(req.http.objsize-hint));
-		}
 		else {
 			set resp.http.e = "Unknown tunable header";
 		}
@@ -248,24 +244,12 @@ client c6 -repeat 1 {
 	expect resp.body == "Value of mem_reserve_chunks must not be negative"
 } -start
 
-client c7 -repeat 1 {
-	txreq -url "/tune" -hdr "objsize-hint: 1MB"
-	rxresp
-	expect resp.status == 200
-	expect resp.body == ""
-	txreq -url "/tune" -hdr "objsize-hint: 1KB"
-	rxresp
-	expect resp.status == 400
-	expect resp.body == "Value of objsize_hint is too small, minimum is 4096"
-} -start
-
 client c1 -wait
 client c2 -wait
 client c3 -wait
 client c4 -wait
 client c5 -wait
 client c6 -wait
-client c7 -wait
 
 varnish v1 -vcl {
 	backend none none;

src/vtc/fellow_vcl.vtc

@@ -40,10 +40,6 @@ varnish v1 -arg "-jnone -p debug=+vclrel -p vsl_mask=+expkill" -vcl {
 			set resp.http.e = fellow.tune(mem_reserve_chunks =
 				std.integer(req.http.mem-reserve-chunks));
 		}
-		else if (req.http.objsize-hint) {
-			set resp.http.e = fellow.tune(objsize_hint =
-				std.bytes(req.http.objsize-hint));
-		}
 		else {
 			set resp.http.e = "Unknown tunable header";
 		}
@@ -251,21 +247,9 @@ client c6 -repeat 1 {
 	expect resp.body == "Value of mem_reserve_chunks must not be negative"
 } -start
 
-client c7 -repeat 1 {
-	txreq -url "/tune" -hdr "objsize-hint: 1MB"
-	rxresp
-	expect resp.status == 200
-	expect resp.body == ""
-	txreq -url "/tune" -hdr "objsize-hint: 1KB"
-	rxresp
-	expect resp.status == 400
-	expect resp.body == "Value of objsize_hint is too small, minimum is 4096"
-} -start
-
 client c1 -wait
 client c2 -wait
 client c3 -wait
 client c4 -wait
 client c5 -wait
 client c6 -wait
-client c7 -wait

src/vtc/unstable/fellow_vcl.vtc

@@ -40,10 +40,6 @@ varnish v1 -arg "-jnone -p debug=+vclrel -p vsl_mask=+expkill" -vcl {
 			set resp.http.e = fellow.tune(mem_reserve_chunks =
 				std.integer(req.http.mem-reserve-chunks));
 		}
-		else if (req.http.objsize-hint) {
-			set resp.http.e = fellow.tune(objsize_hint =
-				std.bytes(req.http.objsize-hint));
-		}
 		else {
 			set resp.http.e = "Unknown tunable header";
 		}
@@ -249,24 +245,12 @@ client c6 -repeat 1 {
 	expect resp.body == "Value of mem_reserve_chunks must not be negative"
 } -start
 
-client c7 -repeat 1 {
-	txreq -url "/tune" -hdr "objsize-hint: 1MB"
-	rxresp
-	expect resp.status == 200
-	expect resp.body == ""
-	txreq -url "/tune" -hdr "objsize-hint: 1KB"
-	rxresp
-	expect resp.status == 400
-	expect resp.body == "Value of objsize_hint is too small, minimum is 4096"
-} -start
-
 client c1 -wait
 client c2 -wait
 client c3 -wait
 client c4 -wait
 client c5 -wait
 client c6 -wait
-client c7 -wait
 
 # unconfigure fellow
 varnish v1 -vcl {