Merge pull request #333 in HDFFV/hdf5 from merge_page_buffering_07 to develop

* commit '4fad103187db9095afc8eab90b5f5544feb1d19b':
  Bring changes to I/O parameters from page_buffering branch.
  Merge in reentrency changes to "make space in cache" from page_buffering branch.
  Minor cleanups and bring over "prefetched dirty" fixes for entries loaded from a cache image.
  Remove some usage of "prefetched_dirty" flag (which hasn't been merged from the page_buffering branch yet.  Also, bring over improvements to flush candidate entries for parallel code.
  Align with incoming page buffering changes: minor cleanups, centralize removing entries from collective metadata read list

1 files changed, 30 insertions, 0 deletions

diff --git a/src/H5Cpkg.h b/src/H5Cpkg.h
index 5b923e9..321f1fb 100644
--- a/src/H5Cpkg.h
+++ b/src/H5Cpkg.h
@@ -4104,6 +4104,23 @@ typedef struct H5C_tag_info_t {
  *		of changes to the file driver info superblock extension
  *		management code needed to support rings.
  *
+ * msic_in_progress: As the metadata cache has become re-entrant, and as
+ *              the free space manager code has become more tightly 
+ *              integrated with the metadata cache, it is possible that 
+ *              a call to H5C_insert_entry() may trigger a call to 
+ *              H5C_make_space_in_cache(), which, via H5C__flush_single_entry()
+ *              and client callbacks, may trigger an infinite regression
+ *              of calls to H5C_make_space_in_cache().
+ *
+ *              The msic_in_progress boolean flag is used to detect this,
+ *              and prevent the infinite regression that would otherwise
+ *              occur.
+ *
+ *              Note that this is issue is not hypothetical -- this field 
+ *              was added 2/16/17 to address this issue when it was 
+ *              exposed by modifications to test/fheap.c to cause it to 
+ *              use paged allocation.
+ *
  * resize_ctl:	Instance of H5C_auto_size_ctl_t containing configuration
  * 		data for automatic cache resizing.
  *
@@ -4500,12 +4517,22 @@ typedef struct H5C_tag_info_t {
  * total_entries_skipped_in_msic: Number of clean entries skipped while
  *              enforcing the min_clean_fraction in H5C__make_space_in_cache().
  *
+ * total_dirty_pf_entries_skipped_in_msic: Number of dirty prefetched entries
+ *              skipped in H5C__make_space_in_cache().  Note that this can 
+ *              only occur when a file is opened R/O with a cache image
+ *              containing dirty entries.
+ *
  * total_entries_scanned_in_msic: Number of clean entries skipped while
  *              enforcing the min_clean_fraction in H5C__make_space_in_cache().
  *
  * max_entries_skipped_in_msic: Maximum number of clean entries skipped
  *              in any one call to H5C__make_space_in_cache().
  *
+ * max_dirty_pf_entries_skipped_in_msic: Maximum number of dirty prefetched
+ *              entries skipped in any one call to H5C__make_space_in_cache().
+ *              Note that this can only occur when the file is opened 
+ *              R/O with a cache image containing dirty entries.
+ *
  * max_entries_scanned_in_msic: Maximum number of entries scanned over
  *              in any one call to H5C__make_space_in_cache().
  *
@@ -4733,6 +4760,7 @@ struct H5C_t {
     hbool_t			cache_full;
     hbool_t			size_decreased;
     hbool_t			resize_in_progress;
+    hbool_t			msic_in_progress;
     H5C_auto_size_ctl_t		resize_ctl;
 
     /* Fields for epoch markers used in automatic cache size adjustment */
@@ -4822,8 +4850,10 @@ struct H5C_t {
     /* Fields for tracking 'make space in cache' (msic) operations */
     int64_t                     calls_to_msic;
     int64_t                     total_entries_skipped_in_msic;
+    int64_t                     total_dirty_pf_entries_skipped_in_msic;
     int64_t                     total_entries_scanned_in_msic;
     int32_t                     max_entries_skipped_in_msic;
+    int32_t                     max_dirty_pf_entries_skipped_in_msic;
     int32_t                     max_entries_scanned_in_msic;
     int64_t                     entries_scanned_to_make_space;