Commit de46c190 authored by Zardosht Kasheff's avatar Zardosht Kasheff Committed by Yoni Fogel
Browse files

[t:4557], add comments from code review of query code 

git-svn-id: file:///svn/toku/tokudb@40169 c7de825b-a66e-492c-adef-691d508d4ae1
parent 6a544feb

newbrt/brt-internal.h

+2 −1
Original line number Diff line number Diff line
@@ -351,7 +351,7 @@ struct brt_header { 
    struct brt_header * checkpoint_header;

    CACHEFILE cf;

    // lock used by a thread to pin the root node to start a descent into 

    // the tree. This lock protects the blocknum of the root node. Any 

    // the tree. This lock protects the blocknum of the root node (root_blocknum). Any 

    // thread that wants to descend down the tree starting at the root 

    // must grab this lock before pinning the root.

    toku_pthread_mutex_t tree_lock;
@@ -377,6 +377,7 @@ struct brt_header { 
    int64_t num_blocks_to_upgrade_14;   // Number of v14 blocks still not newest version. 

    unsigned int nodesize;

    unsigned int basementnodesize;

    // this field is protected by tree_lock, see comment for tree_lock

    BLOCKNUM root_blocknum;            // roots of the dictionary

    unsigned int flags;

    DESCRIPTOR_S descriptor;

newbrt/cachetable.c

+7 −1
Original line number Diff line number Diff line
@@ -2223,7 +2223,9 @@ int toku_cachetable_get_and_pin_with_dep_pairs ( 
            nb_mutex_write_lock(&p->nb_mutex, ct->mutex);

            pair_touch(p);

            // used for shortcutting a path to getting the user the data

            // helps scalability for in-memory workloads

            // helps scalability for in-memory workloads by not holding the cachetable lock

            // when calling pf_req_callback, and if possible, returns the PAIR to the user without

            // reacquiring the cachetable lock

            BOOL fast_checkpointing = (resolve_checkpointing_fast(p) && num_dependent_pairs == 0);

            if (p->checkpoint_pending && fast_checkpointing) write_locked_pair_for_checkpoint(ct, p);

            cachetable_unlock(ct);
@@ -2525,6 +2527,10 @@ int toku_cachetable_get_and_pin_nonblocking ( 
                    write_locked_pair_for_checkpoint(ct, p);

                }

                pair_touch(p);

                // release the cachetable lock before calling pf_req_callback

                // helps scalability for in-memory workloads by not holding the cachetable lock

                // when calling pf_req_callback, and if possible, returns the PAIR to the user without

                // reacquiring the cachetable lock

                cachetable_unlock(ct);

                BOOL partial_fetch_required = pf_req_callback(p->value,read_extraargs);

                //