archive/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2025-08-28 07:14:30 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

7158800: Improve storage of symbol tables

Browse source 
Use an alternate version of hashing algorithm for symbol string tables and after a certain bucket size to improve performance

Reviewed-by: pbk, kamg, dlong, kvn, fparain
This commit is contained in:
Coleen Phillimore 2012-06-13 19:52:59 -04:00
parent 7c17e9e75b
commit 55b09e7016
17 changed files with 32031 additions and 55 deletions
Download patch file Download diff file Expand all files Collapse all files

39
hotspot/src/share/vm/utilities/hashtable.hpp
View file

@ -159,8 +159,6 @@ public:
// Reverse the order of elements in each of the buckets.
void reverse();
static unsigned int hash_symbol(const char* s, int len);
private:
// Instance variables
int _table_size;
@ -179,6 +177,11 @@ protected:
void verify_lookup_length(double load);
#endif
enum {
rehash_count = 100,
rehash_multiple = 60
};
void initialize(int table_size, int entry_size, int number_of_entries);
// Accessor
@ -193,6 +196,34 @@ protected:
// Table entry management
BasicHashtableEntry* new_entry(unsigned int hashValue);
// Check that the table is unbalanced
bool check_rehash_table(int count);
// Used when moving the entry to another table
// Clean up links, but do not add to free_list
void unlink_entry(BasicHashtableEntry* entry) {
entry->set_next(NULL);
--_number_of_entries;
}
// Move over freelist and free block for allocation
void copy_freelist(BasicHashtable* src) {
_free_list = src->_free_list;
src->_free_list = NULL;
_first_free_entry = src->_first_free_entry;
src->_first_free_entry = NULL;
_end_block = src->_end_block;
src->_end_block = NULL;
}
// Free the buckets in this hashtable
void free_buckets() {
if (NULL != _buckets) {
FREE_C_HEAP_ARRAY(HashtableBucket, _buckets);
_buckets = NULL;
}
}
public:
int table_size() { return _table_size; }
void set_entry(int index, BasicHashtableEntry* entry);
@ -249,6 +280,10 @@ protected:
HashtableEntry<T>** bucket_addr(int i) {
return (HashtableEntry<T>**)BasicHashtable::bucket_addr(i);
}
// Function to move these elements into the new table.
void move_to(Hashtable<T>* new_table);
virtual unsigned int new_hash(T) { ShouldNotReachHere(); return 0; } // should be overridden
};